Adobe Reader does not verify electronic signature

[BCGL]

Adobe Reader installed on one of the computers does not verify electronic signatures. On another computer, the same program verifies the signature and confirms its correctness. I did an update of the program, certificates and it still does not work. What else can I do?

[MikelKlink]

What exactly is the message with which that Adobe Reader instance rejects the signatures in question? Can you share an example PDF?

[BCGL]

Attached is a document signed with a qualified signature. On all other computers it displays "Signed. All signatures are correct." Unfortunately, on this one computer there is the same file and it displays "Al least one signature has problems".
I also noticed that on the other computers among the certificates there is a certificate starting with a string of digits and ending with the email address of the person to whom the computer is assigned (screen attached). And on the computer where Adobe cannot verify these signatures there is nothing similar.

[MikelKlink]

Ok, when I validate that signature, open the context menu of that signature in the signature panel on the left, and select "Show Signature Properties...", I get

What does the problem computer show there? (Please make sure to set the Adobe Reader language to English for the screen shot.)

[BCGL]

Attached are screenshots.

[MikelKlink]

Ok, that looks like the copy of the EUTL that Adobe Reader is using is outdated or broken.

Could you select Preferences --> Trust Manager? The bottom-most frame should look like this:

Please press the Update Now button.

[BCGL]

Unfortunately, it doesn't help. I also did this before and it didn't do anything either. Now when I updated, a message like the one attached appeared for a while. But now it is again as it was.

[MikelKlink]

Could you check whether the issuer of the certificate is trusted in your installation?

I.e. in the Preferences select "Signatures", in the "Identities & Trusted Certificates" press "More...", select "Trusted Certificates", and search for entries for "COPE SZAFIR - Kwalifikowany". Is there this one?

As you see in the screen shot, I have two entries for that name here, differing in their issuer name and their validity time range.

Also can you check whether your verification settings differ from the following ones? You find them under Preferences --> Signatures --> Verification: More...

[BCGL]

I have the first screen different (attached), the second is the same.

[MikelKlink]

Ah, that shows that that Adobe Reader instance integrates neither the AATL nor the EUTL certificates even though you explicitly triggered updates thereof.(by clicking "Update now" in the trust manager preferences).

I haven't had that issue myself yet, so maybe someone else can help here.

My guess would be either that the computer in question is not allowed network access to the download sites of the AATL and EUTL or that the files in which Adobe Reader locally stores those trusted certificates are somehow damaged or not writeable.

In the former case giving the computer full access to the internet should suffice, in the latter case a repair of the installation or even an uninstall of Adobe Reader, a cleanup of left-behind Adobe configuration files, and a fresh re-install of the Reader should do it.

[JR Boulay]

[MOVED TO THE ACROBAT READER DISCUSSIONS]