PDF file preview issue
Posted by graceyin39@reddit | sysadmin | View on Reddit | 20 comments
Hi,
One of my users is unable to preview PDF files and receives the following message:
“The file you are attempting to preview could harm your computer. If you trust the file and the source you received it from, open it to view its contents.”
The PDFs are stored on a network shared drive. I’m able to preview the same files on my computer without any issues.
From my research, this appears to be related to a Microsoft update released last October. The suggested workaround is to manually “unblock” each file. However, the user reviews a large number of PDFs every day, so unblocking them one by one isn’t practical.
I also tried the PowerShell solution mentioned in the thread below, but it didn’t resolve the issue:
https://www.reddit.com/r/WindowsHelp/comments/1o7gml8/file_explorer_preview_stopped_with_the_most/
What I don’t understand is why some computers are affected while others are not, even though they are in the same domain and managed by the same update server. They should all be receiving the same updates.
Any help would be greatly appreciated.
Thanks!
Grimend@reddit
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3]
"180F"=dword:00000000
This will soft your issue.
St0nywall@reddit
If unblocking the files makes it work, then why not do that?
Unblocks all files in the folder recursively.
graceyin39@reddit (OP)
This will only unlock the existing files, not the new files. The job my user does requires she downloads a lot of PDF files every day.
St0nywall@reddit
Then add the sites she downloads to to the trusted site list. Or disable that security feature for her.... or keep the security feature and make a shortcut on the desktop for her to unprotect the files in a certain folder.
Lots of options, pick one and go with it. If there's an extra step for her, then she gets to deal with it like an adult doing her job.
graceyin39@reddit (OP)
Tried adding the site to the trusted site, the error is gone, but preview is blank.
graceyin39@reddit (OP)
Without preview feature, her production is significantly reduced.
justaguyonthebus@reddit
You need to fix the initial download. Once it's flagged as blocked, you actually have to unblock it. If they are all coming from the same site, mark that site as trusted.
PDQ_Brockstar@reddit
I saw you mentioned that you tried the PowerShell suggestion in that post, but did you also try the registry edit recommended in the comments?
graceyin39@reddit (OP)
Yes I did, it didn’t help
songbird42-@reddit
Add the file location to Trusted Sites in Internet Options.
graceyin39@reddit (OP)
it's a network shared drive like \\MyFileServer\MyFile. I can't add it to Trust Sites. I added it to local Intranet site, but it didn't help.
songbird42-@reddit
You need to uncheck the requirement that it’s a http
graceyin39@reddit (OP)
Thanks! The error message is gone now, but the preview still didn't show up. It's blank now.
songbird42-@reddit
Is it like that for all the files? Is a default app set for pdfs? Reboot?
graceyin39@reddit (OP)
I rebooted the computer, still the same. Actually, the preview will appear very quickly and then disappear, then stay blank
Akai-Raion@reddit
Does changing the default app make a difference like changing to Chrome? Also, there is an option in Adobe to enable previews in explorer, Adobe> Edit > Preferences > General, and then check “Enable PDF thumbnail previews in Windows Explorer” see if that helps
songbird42-@reddit
Rip I’m sorry. I’d have to mess around with it to figure it out. Does Copilot have any insight? Sometimes with Windows problems I do ask Copilot since it’s a Windows tool.
graceyin39@reddit (OP)
yes to all files. The default app is Adobe Acrobat. I will try rebooting now
nitroman89@reddit
My coworker ran into this issue with a user. Powertools will get it working in File Explorer but won't work in like Outlook.
Otherwise, I found that you would have to do some regkey change and then run a powershell script to unblock the files in the properties window.
songbird42-@reddit
You need to uncheck the requirement that it’s a http