Windows 11 Home, 22H2

Edge, Firefox, Brave, SR Iron installed.

Windows File Explorer set to show previews.

..csv, .doc, .xls, .jpg files all automatically show previews just fine when
selected (left click) in File Explorer

When selected in File Explorer, this message is displayed in what would be
the preview screen:

"This file can't be previewed because of an error in the PDF Preview
Handler."

Adobe Acrobat Free Reader is not installed. I did install it, and set it
as the default pdf reader, but still no good. What this did was to display
nothing in the preview display window. I uninstalled it, and did a system
recovery, so I'm back to "This file can't be previewed because of an error
in the PDF Preview Handler."

I've researched, and nothing I've found seems to correct this error.

Any ideas?

TIA

On 6/2/2023 11:33 PM, Boris wrote:
> Windows 11 Home, 22H2
>
> Edge, Firefox, Brave, SR Iron installed.
>
> Windows File Explorer set to show previews.
>
> .csv, .doc, .xls, .jpg files all automatically show previews just fine when
> selected (left click) in File Explorer
>
> When selected in File Explorer, this message is displayed in what would be
> the preview screen:
>
> "This file can't be previewed because of an error in the PDF Preview
> Handler."
>
> Adobe Acrobat Free Reader is not installed. I did install it, and set it
> as the default pdf reader, but still no good. What this did was to display
> nothing in the preview display window. I uninstalled it, and did a system
> recovery, so I'm back to "This file can't be previewed because of an error
> in the PDF Preview Handler."
>
> I've researched, and nothing I've found seems to correct this error.
>
> Any ideas?
>
> TIA

Did you install 32-bit or 64-bit version ?

The 64-bit version is more likely to have a Preview handler.

But let's check something else before working on that.

Edit : Preferences : General_Tab : Enable PDF thumbnail previews (15 tick boxes down)

Paul

On 03/06/2023 04:33, Boris wrote:
> Windows 11 Home, 22H2
>
> Edge, Firefox, Brave, SR Iron installed.
>
> Windows File Explorer set to show previews.
>
> .csv, .doc, .xls, .jpg files all automatically show previews just fine when
> selected (left click) in File Explorer
>
> When selected in File Explorer, this message is displayed in what would be
> the preview screen:
>
> "This file can't be previewed because of an error in the PDF Preview
> Handler."
>
> Adobe Acrobat Free Reader is not installed. I did install it, and set it
> as the default pdf reader, but still no good. What this did was to display
> nothing in the preview display window. I uninstalled it, and did a system
> recovery, so I'm back to "This file can't be previewed because of an error
> in the PDF Preview Handler."
>
> I've researched, and nothing I've found seems to correct this error.
>
> Any ideas?
>
> TIA

It appears that you are experiencing issues with the PDF preview handler
in Windows File Explorer. Here are a few troubleshooting steps you can
try to resolve the problem:

1. Update Windows: Ensure that your Windows operating system is up to
date. Sometimes, Microsoft releases updates that fix known issues,
including problems with preview handlers.

2. Install Adobe Acrobat Reader DC: While you mentioned that you
installed Adobe Acrobat Free Reader, it's possible that it didn't
properly integrate with the preview handler. I recommend downloading and
installing the latest version of Adobe Acrobat Reader DC from the
official Adobe website. After installation, set it as the default PDF
reader.

3. Repair Adobe Acrobat Reader DC: If you already have Adobe Acrobat
Reader DC installed, you can try repairing the installation. Open the
Control Panel, navigate to "Programs" or "Programs and Features," locate
Adobe Acrobat Reader DC in the list, and select the option to repair or
modify the installation. Follow the prompts to complete the process.

4. Reset File Explorer Preview Settings: You can try resetting the File
Explorer preview settings to their default values. To do this, open the
File Explorer Options by typing "File Explorer Options" in the Start
menu search bar and selecting the appropriate result. In the "File
Explorer Options" window, go to the "View" tab, and click on the "Reset"
button under "Reset File Explorer's preview pane." Click "Apply" and
"OK" to save the changes.

5. Clear Thumbnail Cache: Clearing the thumbnail cache can sometimes
resolve issues with file previews. Open File Explorer and go to the
following folder: `%LocalAppData%\Microsoft\Windows\Explorer`. Delete
all the files with the prefix "thumbcache" or "iconcache". Afterward,
restart your computer.

6. Try Alternative PDF Readers: If the issue persists, you might
consider trying alternative PDF readers that have built-in preview
capabilities, such as Foxit Reader or SumatraPDF. Install one of these
programs, set it as the default PDF reader, and check if the preview
handler works with these applications.

If none of these steps resolve the problem, you may need to seek further
assistance from Microsoft support or explore other online communities
where users discuss Windows-related issues in more detail.

Paul wrote:
> On 6/2/2023 11:33 PM, Boris wrote:
>> Windows 11 Home, 22H2
>>
>> Edge, Firefox, Brave, SR Iron installed.
>>
>> Windows File Explorer set to show previews.
>>
>> .csv, .doc, .xls, .jpg files all automatically show previews just fine
>> when
>> selected (left click) in File Explorer
>>
>> When selected in File Explorer, this message is displayed in what
>> would be
>> the preview screen:
>>
>> "This file can't be previewed because of an error in the PDF Preview
>> Handler."
>>
>> Adobe Acrobat Free Reader is not installed.  I did install it, and set it
>> as the default pdf reader, but still no good.  What this did was to
>> display
>> nothing in the preview display window.  I uninstalled it, and did a
>> system
>> recovery, so I'm back to "This file can't be previewed because of an
>> error
>> in the PDF Preview Handler."
>>
>> I've researched, and nothing I've found seems to correct this error.
>>
>> Any ideas?
>>
>> TIA
>
> Did you install 32-bit or 64-bit version ?
>
> The 64-bit version is more likely to have a Preview handler.
>
> But let's check something else before working on that.
>
>    Edit : Preferences : General_Tab : Enable PDF thumbnail previews (15
> tick boxes down)
>
>   Paul
>
>
>
>
Fyi.

The op noted Adobe Acrobat Reader was installed(not sure which version).

Adobe AR DC Classic or Continous 64-bit latest versions(both updated in
April) afiacs on Win11 Pro 22H2(two devices) do not require the 'Enable
PDF previews' option.
- i.e. File Explorer with Preview Pane enabled shows pdf previews when
either DC Classic or Continuous is configured in Win11 as the default
PDF reader. (Note: Both Edge and Chrome, possibly unrelated but maybe
worthy of mention are not configured to open pdf's in a browser window).

Quite some time ago, I recall a discussion where the Windows(not File)
Explorer had some reported issues with displaying pdf file previews for
PDF Reader applications that did not have a built-in preview
handler(which, at this end, Adobe DC Classic/Continous either have or
Windows 11 provides).

Additionally, their was a subset of that discussion reporting that
Windows Explorer even if a preview handler was present, some devices
required IE to be enabled in Windows Features.
- not sure this relationship was ever proven/disproved then or now
with IE deprecation in Windows.
All I can comment on atm, is my two Windows 11 device do have IE enabled
in Windows Features(for IE Edge mode use[1] and as noted earlier, *do
not* have Adobe AR's 'preview setting' enabled.

I thought about Win11 22H2 history(upgraded from 10 or clean install) as
a potential cause, but ruled that out since my devices are each - one
upgrade, one clean install.
- Note: I did not test anything in a VM.

Maybe the op can provide more info(fixed or additional info)
e.g.
- Adober AR version and updated to current with latest April msp
- IE enabled in Windows Features
- Adober AR configure as the default PDF reader in Win11's Settings
for all supported file types and protocol.

[1] Edge Mode is primarily for one reason on Win11 - my AIO HP printer
settings when accessed in a browser by IP address use IE Edge mode to
override Edge's built-in security hardening. This is forced by
safe-listing the printers ip address in Edge's Default Browser/IE Edge
mode pages option.

--
....w¡ñ§±¤ñ

Paul <nospam@needed.invalid> wrote in news:u5eghb$3flo5$1@dont-email.me:

> On 6/2/2023 11:33 PM, Boris wrote:
>> Windows 11 Home, 22H2
>>
>> Edge, Firefox, Brave, SR Iron installed.
>>
>> Windows File Explorer set to show previews.
>>
>> .csv, .doc, .xls, .jpg files all automatically show previews just
>> fine when selected (left click) in File Explorer
>>
>> When selected in File Explorer, this message is displayed in what
>> would be the preview screen:
>>
>> "This file can't be previewed because of an error in the PDF Preview
>> Handler."
>>
>> Adobe Acrobat Free Reader is not installed. I did install it, and
>> set it as the default pdf reader, but still no good. What this did
>> was to display nothing in the preview display window. I uninstalled
>> it, and did a system recovery, so I'm back to "This file can't be
>> previewed because of an error in the PDF Preview Handler."
>>
>> I've researched, and nothing I've found seems to correct this error.
>>
>> Any ideas?
>>
>> TIA
>
> Did you install 32-bit or 64-bit version ?
>
> The 64-bit version is more likely to have a Preview handler.

The 64-bit version.
>
> But let's check something else before working on that.
>
> Edit : Preferences : General_Tab : Enable PDF thumbnail previews
> (15 tick boxes down)

It is 15 tick boxes down in the View tab, and it is enabled.

No luck.

>
> Paul
>
>
>
>

"...winston" <winstonmvp@gmail.com> wrote in
news:u5frbb$3k3fg$1@dont-email.me:

> Paul wrote:
>> On 6/2/2023 11:33 PM, Boris wrote:
>>> Windows 11 Home, 22H2
>>>
>>> Edge, Firefox, Brave, SR Iron installed.
>>>
>>> Windows File Explorer set to show previews.
>>>
>>> .csv, .doc, .xls, .jpg files all automatically show previews just
>>> fine when
>>> selected (left click) in File Explorer
>>>
>>> When selected in File Explorer, this message is displayed in what
>>> would be
>>> the preview screen:
>>>
>>> "This file can't be previewed because of an error in the PDF Preview
>>> Handler."
>>>
>>> Adobe Acrobat Free Reader is not installed.  I did install it, and
>>> set it as the default pdf reader, but still no good.  What this did
>>> was to display
>>> nothing in the preview display window.  I uninstalled it, and did a
>>> system
>>> recovery, so I'm back to "This file can't be previewed because of an
>>> error
>>> in the PDF Preview Handler."
>>>
>>> I've researched, and nothing I've found seems to correct this error.
>>>
>>> Any ideas?
>>>
>>> TIA
>>
>> Did you install 32-bit or 64-bit version ?
>>
>> The 64-bit version is more likely to have a Preview handler.
>>
>> But let's check something else before working on that.
>>
>>    Edit : Preferences : General_Tab : Enable PDF thumbnail
>> previews (15
>> tick boxes down)
>>
>>   Paul
>>
>>
>>
>>
> Fyi.
>
> The op noted Adobe Acrobat Reader was installed(not sure which
> version).

>
> Adobe AR DC Classic or Continous 64-bit latest versions(both updated
> in April) afiacs on Win11 Pro 22H2(two devices) do not require the
> 'Enable PDF previews' option.

I installed Adobe Acrobat Reader Continuous Release (AARCR),
2023.001.20174, 64-bit, and set to default. I left preview pane
enabled. It worked. I disabled preview, and it didn't work. Renabled,
and it worked again. Seems in my case, preview has to be enabled.
Wonder if it now matters what the .pdf extension is set to use...

With AARCR still installed, and under the above settings, if I set the
..pdf extension, in default applications, to Firefox (and left all other
exstensions to use AARCR), the preview worked. As a matter of fact, I
could set every extension to Firefox, and it still worked fine. (At the
very bottom of the list of default extensions was ACROBAT:URL Protocol.
As you all probably know, it does not present a list of app to reset
to.) But, if I disabled preview, previews didn't work.

I tried the same procedures with FoxIt, set it as the default reader,
and had the same results. Preview pane had to be enabled. Previews
worked fine, even if I reset all the extensions to use FoxIt.

It seems that some sort of pdf reader has to be installed, and preview
has to be enabled (which is default), in order for file explorer to
produce previews. Your results obviously vary. I think it's odd that
Windows 11 does not provide a 'preview handler', if that's what's going
on, and that one had to install another company's reader to get file
explorer to work.

By the way, Internet Explorer Mode is installed and enabled.

> - i.e. File Explorer with Preview Pane enabled shows pdf previews
> when
> either DC Classic or Continuous is configured in Win11 as the default
> PDF reader. (Note: Both Edge and Chrome, possibly unrelated but maybe
> worthy of mention are not configured to open pdf's in a browser
> window).
>
> Quite some time ago, I recall a discussion where the Windows(not File)
> Explorer had some reported issues with displaying pdf file previews
> for PDF Reader applications that did not have a built-in preview
> handler(which, at this end, Adobe DC Classic/Continous either have or
> Windows 11 provides).
>
> Additionally, their was a subset of that discussion reporting that
> Windows Explorer even if a preview handler was present, some devices
> required IE to be enabled in Windows Features.
> - not sure this relationship was ever proven/disproved then or now
> with IE deprecation in Windows.
> All I can comment on atm, is my two Windows 11 device do have IE
> enabled in Windows Features(for IE Edge mode use[1] and as noted
> earlier, *do not* have Adobe AR's 'preview setting' enabled.
>
> I thought about Win11 22H2 history(upgraded from 10 or clean install)
> as a potential cause, but ruled that out since my devices are each -
> one upgrade, one clean install.
> - Note: I did not test anything in a VM.
>
> Maybe the op can provide more info(fixed or additional info)
> e.g.
> - Adober AR version and updated to current with latest April msp
> - IE enabled in Windows Features
> - Adober AR configure as the default PDF reader in Win11's Settings
> for all supported file types and protocol.
>
> [1] Edge Mode is primarily for one reason on Win11 - my AIO HP printer
> settings when accessed in a browser by IP address use IE Edge mode to
> override Edge's built-in security hardening. This is forced by
> safe-listing the printers ip address in Edge's Default Browser/IE Edge
> mode pages option.
>
>

David Brooks <DavidB@nomail.afraid.org> wrote in
news:CrCeM.2346049$MVg8.164719@fx12.iad:

> On 03/06/2023 04:33, Boris wrote:
>> Windows 11 Home, 22H2
>>
>> Edge, Firefox, Brave, SR Iron installed.
>>
>> Windows File Explorer set to show previews.
>>
>> .csv, .doc, .xls, .jpg files all automatically show previews just
>> fine when selected (left click) in File Explorer
>>
>> When selected in File Explorer, this message is displayed in what
>> would be the preview screen:
>>
>> "This file can't be previewed because of an error in the PDF Preview
>> Handler."
>>
>> Adobe Acrobat Free Reader is not installed. I did install it, and
>> set it as the default pdf reader, but still no good. What this did
>> was to display nothing in the preview display window. I uninstalled
>> it, and did a system recovery, so I'm back to "This file can't be
>> previewed because of an error in the PDF Preview Handler."
>>
>> I've researched, and nothing I've found seems to correct this error.
>>
>> Any ideas?
>>
>> TIA
>
>
> It appears that you are experiencing issues with the PDF preview
> handler in Windows File Explorer. Here are a few troubleshooting steps
> you can try to resolve the problem:
>
> 1. Update Windows: Ensure that your Windows operating system is up to
> date. Sometimes, Microsoft releases updates that fix known issues,
> including problems with preview handlers.
>
> 2. Install Adobe Acrobat Reader DC: While you mentioned that you
> installed Adobe Acrobat Free Reader, it's possible that it didn't
> properly integrate with the preview handler. I recommend downloading
> and installing the latest version of Adobe Acrobat Reader DC from the
> official Adobe website. After installation, set it as the default PDF
> reader.

This worked. I guess AARDC installs a preview handler...but read my
reply to Winston.

>
> 3. Repair Adobe Acrobat Reader DC: If you already have Adobe Acrobat
> Reader DC installed, you can try repairing the installation. Open the
> Control Panel, navigate to "Programs" or "Programs and Features,"
> locate Adobe Acrobat Reader DC in the list, and select the option to
> repair or modify the installation. Follow the prompts to complete the
> process.
>
> 4. Reset File Explorer Preview Settings: You can try resetting the
> File Explorer preview settings to their default values. To do this,
> open the File Explorer Options by typing "File Explorer Options" in
> the Start menu search bar and selecting the appropriate result. In the
> "File Explorer Options" window, go to the "View" tab, and click on the
> "Reset" button under "Reset File Explorer's preview pane." Click
> "Apply" and "OK" to save the changes.
>
> 5. Clear Thumbnail Cache: Clearing the thumbnail cache can sometimes
> resolve issues with file previews. Open File Explorer and go to the
> following folder: `%LocalAppData%\Microsoft\Windows\Explorer`. Delete
> all the files with the prefix "thumbcache" or "iconcache". Afterward,
> restart your computer.
>
> 6. Try Alternative PDF Readers: If the issue persists, you might
> consider trying alternative PDF readers that have built-in preview
> capabilities, such as Foxit Reader or SumatraPDF. Install one of these
> programs, set it as the default PDF reader, and check if the preview
> handler works with these applications.

I tried FoxIt. It worked just like AARDC. I guess FoxIt also installs
a preview handler.

It seems that, for me, a preview handler has to be enabled in file
explorer, and as long as a pdf reader with a previewer, is also
installed (and I'm going to assume the installed reader(s) includs a pdf
handler), that file explorer will previwe pdfs.

>
> If none of these steps resolve the problem, you may need to seek
> further assistance from Microsoft support or explore other online
> communities where users discuss Windows-related issues in more detail.

On 6/3/2023 9:53 PM, Boris wrote:
> "...winston" <winstonmvp@gmail.com> wrote in
> news:u5frbb$3k3fg$1@dont-email.me:
>
>> Paul wrote:
>>> On 6/2/2023 11:33 PM, Boris wrote:
>>>> Windows 11 Home, 22H2
>>>>
>>>> Edge, Firefox, Brave, SR Iron installed.
>>>>
>>>> Windows File Explorer set to show previews.
>>>>
>>>> .csv, .doc, .xls, .jpg files all automatically show previews just
>>>> fine when
>>>> selected (left click) in File Explorer
>>>>
>>>> When selected in File Explorer, this message is displayed in what
>>>> would be
>>>> the preview screen:
>>>>
>>>> "This file can't be previewed because of an error in the PDF Preview
>>>> Handler."
>>>>
>>>> Adobe Acrobat Free Reader is not installed.  I did install it, and
>>>> set it as the default pdf reader, but still no good.  What this did
>>>> was to display
>>>> nothing in the preview display window.  I uninstalled it, and did a
>>>> system
>>>> recovery, so I'm back to "This file can't be previewed because of an
>>>> error
>>>> in the PDF Preview Handler."
>>>>
>>>> I've researched, and nothing I've found seems to correct this error.
>>>>
>>>> Any ideas?
>>>>
>>>> TIA
>>>
>>> Did you install 32-bit or 64-bit version ?
>>>
>>> The 64-bit version is more likely to have a Preview handler.
>>>
>>> But let's check something else before working on that.
>>>
>>>    Edit : Preferences : General_Tab : Enable PDF thumbnail
>>> previews (15
>>> tick boxes down)
>>>
>>>   Paul
>>>
>>>
>>>
>>>
>> Fyi.
>>
>> The op noted Adobe Acrobat Reader was installed(not sure which
>> version).
>
>
>>
>> Adobe AR DC Classic or Continous 64-bit latest versions(both updated
>> in April) afiacs on Win11 Pro 22H2(two devices) do not require the
>> 'Enable PDF previews' option.
>
> I installed Adobe Acrobat Reader Continuous Release (AARCR),
> 2023.001.20174, 64-bit, and set to default. I left preview pane
> enabled. It worked. I disabled preview, and it didn't work. Renabled,
> and it worked again. Seems in my case, preview has to be enabled.
> Wonder if it now matters what the .pdf extension is set to use...
>
> With AARCR still installed, and under the above settings, if I set the
> .pdf extension, in default applications, to Firefox (and left all other
> exstensions to use AARCR), the preview worked. As a matter of fact, I
> could set every extension to Firefox, and it still worked fine. (At the
> very bottom of the list of default extensions was ACROBAT:URL Protocol.
> As you all probably know, it does not present a list of app to reset
> to.) But, if I disabled preview, previews didn't work.
>
> I tried the same procedures with FoxIt, set it as the default reader,
> and had the same results. Preview pane had to be enabled. Previews
> worked fine, even if I reset all the extensions to use FoxIt.
>
> It seems that some sort of pdf reader has to be installed, and preview
> has to be enabled (which is default), in order for file explorer to
> produce previews. Your results obviously vary. I think it's odd that
> Windows 11 does not provide a 'preview handler', if that's what's going
> on, and that one had to install another company's reader to get file
> explorer to work.
>
> By the way, Internet Explorer Mode is installed and enabled.
>
>> - i.e. File Explorer with Preview Pane enabled shows pdf previews
>> when
>> either DC Classic or Continuous is configured in Win11 as the default
>> PDF reader. (Note: Both Edge and Chrome, possibly unrelated but maybe
>> worthy of mention are not configured to open pdf's in a browser
>> window).
>>
>> Quite some time ago, I recall a discussion where the Windows(not File)
>> Explorer had some reported issues with displaying pdf file previews
>> for PDF Reader applications that did not have a built-in preview
>> handler(which, at this end, Adobe DC Classic/Continous either have or
>> Windows 11 provides).
>>
>> Additionally, their was a subset of that discussion reporting that
>> Windows Explorer even if a preview handler was present, some devices
>> required IE to be enabled in Windows Features.
>> - not sure this relationship was ever proven/disproved then or now
>> with IE deprecation in Windows.
>> All I can comment on atm, is my two Windows 11 device do have IE
>> enabled in Windows Features(for IE Edge mode use[1] and as noted
>> earlier, *do not* have Adobe AR's 'preview setting' enabled.
>>
>> I thought about Win11 22H2 history(upgraded from 10 or clean install)
>> as a potential cause, but ruled that out since my devices are each -
>> one upgrade, one clean install.
>> - Note: I did not test anything in a VM.
>>
>> Maybe the op can provide more info(fixed or additional info)
>> e.g.
>> - Adober AR version and updated to current with latest April msp
>> - IE enabled in Windows Features
>> - Adober AR configure as the default PDF reader in Win11's Settings
>> for all supported file types and protocol.
>>
>> [1] Edge Mode is primarily for one reason on Win11 - my AIO HP printer
>> settings when accessed in a browser by IP address use IE Edge mode to
>> override Edge's built-in security hardening. This is forced by
>> safe-listing the printers ip address in Edge's Default Browser/IE Edge
>> mode pages option.

https://learn.microsoft.com/en-us/windows/powertoys/file-explorer

"Warning

Enabling the preview handlers will override other preview handlers
already installed - there have been reports of incompatibility between
Outlook and the PDF Preview Handler."

( https://github.com/microsoft/PowerToys then click File Explorer AddOns)

"Requirements

Windows 11 or Windows 10...

Our installer will install the following items:
Microsoft Edge WebView2 Runtime bootstrapper.
This will install the latest version.
"

*******

Webview2 provides services to the OS. MSEdge is in the name.

The MSEdge web browser is a separate set of processes. It can
be killed using Task Manager, without affecting Webview2 similar
processes (similar in number).

What the above suggests, is the PDF provider can be (in mob terms)
"bumped off".

Multiple preview/thumbnail providers cannot be used at the
same time, because when a request is made to the COM object,
"something" has to answer, and it's not a pool of choices and
random mayhem. The act of killing off a provider, invalidates
the cache, and that's why multiple of them running might not
be all that clever.

So that's the info I extract from the PowerToys project.

Paul

Boris wrote:
> "...winston" <winstonmvp@gmail.com> wrote in
> news:u5frbb$3k3fg$1@dont-email.me:
>
>> Paul wrote:
>>> On 6/2/2023 11:33 PM, Boris wrote:
>>>> Windows 11 Home, 22H2
>>>>
>>>> Edge, Firefox, Brave, SR Iron installed.
>>>>
>>>> Windows File Explorer set to show previews.
>>>>
>>>> .csv, .doc, .xls, .jpg files all automatically show previews just
>>>> fine when
>>>> selected (left click) in File Explorer
>>>>
>>>> When selected in File Explorer, this message is displayed in what
>>>> would be
>>>> the preview screen:
>>>>
>>>> "This file can't be previewed because of an error in the PDF Preview
>>>> Handler."
>>>>
>>>> Adobe Acrobat Free Reader is not installed.  I did install it, and
>>>> set it as the default pdf reader, but still no good.  What this did
>>>> was to display
>>>> nothing in the preview display window.  I uninstalled it, and did a
>>>> system
>>>> recovery, so I'm back to "This file can't be previewed because of an
>>>> error
>>>> in the PDF Preview Handler."
>>>>
>>>> I've researched, and nothing I've found seems to correct this error.
>>>>
>>>> Any ideas?
>>>>
>>>> TIA
>>>
>>> Did you install 32-bit or 64-bit version ?
>>>
>>> The 64-bit version is more likely to have a Preview handler.
>>>
>>> But let's check something else before working on that.
>>>
>>>    Edit : Preferences : General_Tab : Enable PDF thumbnail
>>> previews (15
>>> tick boxes down)
>>>
>>>   Paul
>>>
>>>
>>>
>>>
>> Fyi.
>>
>> The op noted Adobe Acrobat Reader was installed(not sure which
>> version).
>
>
>>
>> Adobe AR DC Classic or Continous 64-bit latest versions(both updated
>> in April) afiacs on Win11 Pro 22H2(two devices) do not require the
>> 'Enable PDF previews' option.
>
> I installed Adobe Acrobat Reader Continuous Release (AARCR),
> 2023.001.20174, 64-bit, and set to default. I left preview pane
> enabled. It worked. I disabled preview, and it didn't work. Renabled,
> and it worked again. Seems in my case, preview has to be enabled.
> Wonder if it now matters what the .pdf extension is set to use...
>
> With AARCR still installed, and under the above settings, if I set the
> .pdf extension, in default applications, to Firefox (and left all other
> exstensions to use AARCR), the preview worked. As a matter of fact, I
> could set every extension to Firefox, and it still worked fine. (At the
> very bottom of the list of default extensions was ACROBAT:URL Protocol.
> As you all probably know, it does not present a list of app to reset
> to.) But, if I disabled preview, previews didn't work.
>
> I tried the same procedures with FoxIt, set it as the default reader,
> and had the same results. Preview pane had to be enabled. Previews
> worked fine, even if I reset all the extensions to use FoxIt.
>
> It seems that some sort of pdf reader has to be installed, and preview
> has to be enabled (which is default), in order for file explorer to
> produce previews. Your results obviously vary. I think it's odd that
> Windows 11 does not provide a 'preview handler', if that's what's going
> on, and that one had to install another company's reader to get file
> explorer to work.
>
> By the way, Internet Explorer Mode is installed and enabled.
>
>> - i.e. File Explorer with Preview Pane enabled shows pdf previews
>> when
>> either DC Classic or Continuous is configured in Win11 as the default
>> PDF reader. (Note: Both Edge and Chrome, possibly unrelated but maybe
>> worthy of mention are not configured to open pdf's in a browser
>> window).
>>
>> Quite some time ago, I recall a discussion where the Windows(not File)
>> Explorer had some reported issues with displaying pdf file previews
>> for PDF Reader applications that did not have a built-in preview
>> handler(which, at this end, Adobe DC Classic/Continous either have or
>> Windows 11 provides).
>>
>> Additionally, their was a subset of that discussion reporting that
>> Windows Explorer even if a preview handler was present, some devices
>> required IE to be enabled in Windows Features.
>> - not sure this relationship was ever proven/disproved then or now
>> with IE deprecation in Windows.
>> All I can comment on atm, is my two Windows 11 device do have IE
>> enabled in Windows Features(for IE Edge mode use[1] and as noted
>> earlier, *do not* have Adobe AR's 'preview setting' enabled.
>>
>> I thought about Win11 22H2 history(upgraded from 10 or clean install)
>> as a potential cause, but ruled that out since my devices are each -
>> one upgrade, one clean install.
>> - Note: I did not test anything in a VM.
>>
>> Maybe the op can provide more info(fixed or additional info)
>> e.g.
>> - Adober AR version and updated to current with latest April msp
>> - IE enabled in Windows Features
>> - Adober AR configure as the default PDF reader in Win11's Settings
>> for all supported file types and protocol.
>>
>> [1] Edge Mode is primarily for one reason on Win11 - my AIO HP printer
>> settings when accessed in a browser by IP address use IE Edge mode to
>> override Edge's built-in security hardening. This is forced by
>> safe-listing the printers ip address in Edge's Default Browser/IE Edge
>> mode pages option.
>>
>>
>
Thanks for the update.
Yes, apparently some variation.

On Win 10 Pro 22H2, Surface 3, with ADBE Reader DC Classic installed(it
previously had AR 11.x), the preview pane option, like my Win11 with DC
Classic and Continuous does not require the AR preview setting enabled
for pdf previewing in File Explorer.

Yet, my ancient rarely used Acer 5742 Win10 Pro 21H2(never got around to
updating it, since no longer used for much than some older, no longer
needed installed software Office 2019 H/B perpetual), but not replaced
with M365 Family Office on all my other devices), with an earlier
build(not msp updated) of DC Classic with the exact same default apps
and settings as the Win11 Pro 22H2 devices *does require* the ADBE
Reader preview setting to be enabled.
Note: This device also has Foxit Reader(an older version) installed.

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