DDE error with latest version of acrobat reader

[Guest]

Using latest version of Reader DC (2019.010.20098), been having a problem lately with multiple customers getting DDE errors when trying to open a PDF.

this has been on multiple platforms Server 2012 R2 and Server 2016.    I've tried uninstalling and re-installing, but the problem eventually comes back.  I've tried running a repair operation, but again the issue has eventually came back.

I've seen the articles that claim it's an issue with a virus scanner, but just using the standard windows defender.  definitions are current. 

It's not consistent either, sometimes the customers will be able to load PDFs just fine,  but when they can't, I usually see many instances of AcrRdr32.exe running and I have to end task them all, then they can open a pdf again...until the next time it happens.

Also another thing I've noticed is that even when you're opening a single PDF,  there are two instances of AcrRdr32.exe running.  Is this something new with a recent update or something as I don't recall this being the case in the past.

Thank you for any advice you can give.

[AnandSri]

Hello Timmenke,

We're sorry for the trouble you are having with Adobe Reader DC, please refer and try the suggestion from the following help article Fatal error - Acrobat failed to connect to a DDE server

For testing purpose: "Disable Protected Mode at startup, Run in AppContainer and Enhanced Security" from Edit>Preferences>Security(Enhanced)>Click OK, restart the application and check.

Note: Disabling the Protected Mode, Run in AppContainer and Enhanced Security is only for testing purpose, please enable it back irrespective of the result.

Let us know how it goes and share your observation.

Thanks,

Anand Sri.

[Guest]

can protected mode be disabled on a per-computer basis, or does it need to be done on a per-user basis.

Thanks

EDIT:  I found a registry edit to disable it on a per computer basis: 

• Keypath: HKLM\SOFTWARE\Wow6432Node\Policies\Adobe\Acrobat Reader\DC\FeatureLockDown
• Value name: bProtectedMode
• Value type: REG_DWORD
• Value data: 0 to disable or 1 to enable

I'll implement this on a few of our customers and see what we get. 

[Guest]

OK, So I disabled Protected mode on one of our customers, and they report that they haven't had any problems since then.    I would like to re-enable Protected mode, but what are my next steps?

[Test Screen Name]

I have a random thought to throw into the mix. I suspect this could happen if someone runs Reader as administrator. They may not do this specifically; it might be that another app (recently installed? Recently changed to run as administrator?) is running Reader.

[Guest]

With the release of the new version of Acrobat Reader (19.010,20099), I'm going to try restoring Protected Mode on one of our customers to see if there is any difference. 

[Guest · Accepted solution]

Well, after two weeks with no issues.  It looks like it the whole issue can be chalked up to a bug in the previous version which is fixed in this newer version.   Protected Mode appears to cause no issues anymore with the current version. 

[ravikanthc64166242]

Dear All,

With the new version - 2019.012.20034, we seeing this DDE fatal error. Any resolution steps.

Thanks

RK