Preview Pane File Not Found Windows 10

We have noticed the pdf files that won't show a preview has an "x" on the pdf logo beside the file and the files that can be previewed don't have the "x".  Can anyone answer this?

Hello, 

I hope you have solved the issue by now. If not, read below.

I too had similar issue and after hours of digging the internet found the solution. It looks like its neither Windows or Adobe or any other PDF reader per se issue. It’s basically Windows Edge bug which fails to preview the file if “#” is included within the file name. It performs as expected when there is no # sign in the filename.

Anyways solution is running commands to change the preview of the file from Edge to Adobe.

Open Command prompt in Admin rights.

Run these commands to change the default preview from Edge to Adobe.

reg add HKCR\.pdf\ShellEx\{8895b1c6-b41f-4c1c-a562-0d564250836f} /ve /d {DC6EFB56-9CFA-464D-8880-44885D7DC193} /f

Run these commands to stop Edge changing the default preview back to edge.

reg add HKCR\CLSID\{3A84F9C2-6164-485C-A7D9-4B27F8AC009E} /v EnablePreviewHandler /t REG_DWORD /d 0 /f

reg add HKCR\WOW6432Node\CLSID\{3A84F9C2-6164-485C-A7D9-4B27F8AC009E} /v EnablePreviewHandler /t REG_DWORD /d 0 /f

Close the window. It should be solved by now.

My DC was up to date and this issue still happening. I repaired the installation and in my case this worked on 2 different computers

[Fix] PDF Preview Shows Directory Index or ERR_FILE_NOT_FOUND » Winhelponline:
https://www.winhelponline.com/blog/pdf-preview-directory-index-file-not-found/

"Step 2" in the article is important as it stops Edge from resetting the default preview handler.

I'd like to throw my hat in the ring here as someone who is also experiencing this issue.

Updating Adobe Acrobat DC to whatever was the latest version on March 15th seemed to resolve the issue, but it was still present in the free Adobe Reader version.

A week later, I returned to my client's site and they reported that the issue has returned. As no updates were applied to Adobe in the meantime, then I can only assume it IS some issue with Windows itself.

The workaround is to remove the '#' (and maybe other special characters) from the file path, but unfortunately for this client literally every file they work with has the '#' in it and a piece of software they use for processing PDFs requires this, so they are in a catch-22 - they can fix previewing, but it will break other parts of their workflow.

I'm mostly replying here so I can get notified of other replies.

Thanks,

Brian

I have the same issue. Adobe Support is claiming this is a Microsoft Issue. Can anyone confirm?

Removing the # from the file name works but our accounting department uses # in their naming convention so it'd be difficult to change. Thanks

I believe the problem is related to any special character, not just #, that is located anywhere in the file path.  For me 2022.001.20085 still has the problem.

Same issue here. Be curious if they do an update for this. We have a massive amount of file names using the "#" and other characters and there is no way we are changing the file names. So right now we just cant use preview for Adobe files, just have to open the file. Also noticed Adobe preview seems much, much slower as well too now. Our files are sometimes 50 to 100 page files. Better off just opening the file, since as if its trying to pre-load alll the pages just to preview. Adobe preview is almost useless for myself.

is there any other solution other than removing the '#' character in the file name?  

i had the same issue, downloaded the update and it worked for a few days but now i can't preview the files again.  i receive emails with '#' in the file name all the time so that's a lot of files to change just to be able to preview. 

**this is the most helpful thread i have found, regarding this issue... thank you!**

Remove the # from the folder name.