Adobe Reader .PDF file association changed to Edge

[Ultra1000]

Hello,

I'm troubleshooting for a user at our company.

Several times a day, her Windows 10 (version 20H2) resets the default PDF association to Edge.

If she changes the association back to Adobe Acrobat Reader DC, it sticks for an indeterminate amount of time, then Windows pops up another notification saying an error occurred and the PDF file extension was associated to Edge.

I've tried setting the association via the file properties dialog, and also through Default Apps in Settings>Apps>Default Apps. I also tried setting the option in Edge to always open PDF files externally... no luck.

When that didn't work (the association reset again after I finished the session on her computer), I later tried re-installing Adobe Acrobat Reader DC.

I've read countless forums about this issue, and most posts seem to be from as far back as 2015...2018...even some in 2020, but nobody seems to have nailed a solution for this yet.

Does anyone have the slightest idea how to stop Windows from exhibiting this behavior? Preferably, it would be best so it does not reassign any file association on its own.

I saw a glimmer of hope on this Adobe page:

Setting the Default PDF Viewer — DC Deployment Planning and Configuration (adobe.com)

It mentions HKLM (HKEY_LOCAL_MACHINE, from Windows Registry) and a key called DisablePDFHandlerSwitching.  Does anyone know if this key works, and how to implement it into the Registry?

Help please?

[radzmar]

You should check the event viewer of Windows for more details. 

Click the start button, type in "eventvwr" and press [Enter]. Look in the windows logs for errors around the time the association has changed. You might have a serious problem with you operating system.

[Ultra1000]

I opened eventvwr and moved the list to the specific time the computer was rebooted, but there were no errors pertaining to Adobe or PDFs or Edge in the list.

Looks like the operating system doesn't think this is an error.

[DCDCDC2021]

We are experencing the same issue with our Windows 10 20h2 updated devices.

I've tried all of the registry options as well as ensuring we only have Adobe Acrobat REader DC installed (Ran the AdobeAcroCleaner).

Regardless Looks like Edge keep reverting after restarting to be the default PDF viewer.

It also seems there's upswing in people experencing this when I've been trawling via the web. 

Adobe are you getting reports of this via your support teams?

[Dov Isaacs]

Complain to Microsoft. That is their mishegoss! They purposely do that!

[DCDCDC2021]

Hi Dov Isaacs, 

I have opened a case with MS but wanted to see if Adobe is also getting more and more reports of this issue since 20h2 has been released.

Has Adobe support noticed a upward trend in users of their products reporting this issue.

[Dov Isaacs]

Not particularly. This issue has been a royal pain in the tuchas since Windows 10 was initially released!

[Ultra1000]

What's the best way to open an issue with Microsoft?

Can you post a link? I'll open a ticket with them.

Thank you

[Ultra1000]

Yesterday I checked in with the affected user and it wasn't even sending her those notifications anymore.

Every time she reboots the PC, the association is reset to Microsoft Edge quietly.

You can tell first thing because the icons switch from the Adobe icon to the "PDF" Microsoft Edge icon.

I'm trying some registry fixes my colleague found on the superuser forums, maybe that will help...

[Ultra1000]

I've tried several different "registry fixes" to try to change this problem. None have worked.

[FRiC]

If you have a domain. Use SetUserFTA.

[Ultra1000]

Unfortunately this kind of solution wouldn't be approved by our IT security... but thanks for the suggestion, I checked out the blog of the creator of SetUserFTA.

[Ultra1000]

I tried updating my own workstation to Windows 10 version 20H2 (I was running version 2004 before this).

I cannot replicate the problem on my workstation: If I set Adobe Acrobat Reader DC as my default PDF reader, and then reboot, it stays.  On the affected user's machine, it changes back to Edge with every reboot.

I don't think that Adobe software is responsible for this bug on the user's machine.

Anyone have ideas as to what's going on?

I don't believe the affected user has any software installed which would create this behavior so I'm still leaning towards it being a bug in Windows 10... but since I can't replicate the issue, I have my doubts too.

[DCDCDC2021]

Hi all, 

We found that we had turned on Micsofot Edge Browser Profiles within SCCM.

This was causing the Legacy Edge browser to become the default view for web browsers and pdf files.

Even after removing the deployement users where left with settings in their registry that meant legacy Edge continued to be the default viewer for PDF and browers.

So then one of the guys I work with came up with a script to remove the following keys

HKLM:\SOFTWARE\Microsoft\PolicyManager\current\device\ApplicationDefaults
HKLM:\SOFTWARE\Microsoft\PolicyManager\default\ApplicationDefaults\DefaultAssociationsConfiguration
HKLM:\SOFTWARE\Microsoft\PolicyManager\Providers\C982A401-00CD-42DB-A211-9FF2D7C7DED5\default\Device\ApplicationDefaults

The keys very from user but after removing the keys and rebooting with test users this has resolved our issue.

[Scary22531296jgiz]

I would like to quickly jump in with a very similar problem.

This happened to me over night just now.

pdf file association changed to chrome.

Windows 10 forced an over night update (which I have always tried to disable but still happens. It seems W10 will not let me keep that setting indefinately.)

This morning all pdf files now associated with chrome and Windows notification said and update happened and a restart needed to finish it, which I never asked or authorized for.

Again turning off auto updates....again...till how long, it is unknown.
I have changed the file pdf file associations back to Adobe.

This is frustrating. Does anyone know how this can be happening without any authorization from the user?

Thanks in advance for any replies.

SB

[Test Screen Name]

Two things happening.

1. Chrome might take over the PDF association. Not sure whether it always does it or only sometimes.

2. Windows 10 updates (from Microsoft) are not optional. They WILL happen.