Appearance of electronic signatures destroyed (probably due to a corrupted cache)

[Martina23762383dfd2]

We have frequently recurring issues with the correct appearance of our signatures.

The signature itself remain valid, but the appearance is destroyed (see attached examples).

We use mainly Acrobat Reader DC (21.256) for signing (same issues had been seen for Adobe Standard)

We use a certificate issued from the company acting as internal CA .

The appearance is  customized but same effects had been seen for the standard Acrobat appearance as well. 

The problems can be healed by deleting the Adobe Acrobat Cache under „%LOCALAPPDATA%\Adobe\Acrobat\DC“. Investigation showed that the problem might be caused by a corrupt font cache.

User with an affected computer cannot sign any PDF document correctly any more – except a document has already been signed with a correctly displayed signature.

A PDF document that has been signed with a “corrupt” signature, shows all following signature as corrupt not matter if the signer has the display problem or not.

How a computer becomes infected with the problem is unclear.

Just copying an infected cache to a “healthy” computer cannot produce an infection of this computer.

Please see the attachements for examples of destroyed signature appearances.

[AkanchhaS]

Hi Martina,

Thank you for reporting this to us. 

This is a known issue, which has already been reported to our engineering team and they are looking into it on priority. Once we'll hear any update from them, we'll keep you posted. 

Meanwhile, looking at the description given above, it seems that you are working with Acrobat Reader DC (version 21.256)

Acrobat and Reader official update (22.001.20085) is now available. This update will be automatically pushed to all existing installations of Acrobat and Reader. If you want, you may also manually trigger the update early by opening the application and going to Help > Check for Updates>reboot Acrobat.

Try installing the latest update and see if that helps.

Thanks,

Akanchha 

[Amal. · Accepted solution]

Hi there,

Hope you are doing well and sorry to keep you waiting.  We have got some updates from the engineering team as below:

By default MyriadPro-Regular font is used for signing. The issue might arise if the font which is used for signing is present under C:\Windows\Fonts but is a shortcut linking to other software's cache.

So, let's try out a few steps and check the behavior:

1. Please check if the same font is present under C:\Windows\Fonts
2. If present,  Is it a font shortcut?
3. Uninstall the MyriadPro-Regular font from the Windows Fonts directory (C:\Windows\Fonts ) and see the behavior.
4. Install the Adobe provided MyriadPro-Regular font into the Windows Fonts directory and check the behavior.
   
   If it still doesn't work: please try cleaning Local app data cache here  %LOCALAPPDATA%\Adobe\Acrobat\<track> and reboot the computer once and check.
   

Let us know how it goes.

Regards

Amal

[Martina23762383dfd2]

Dear Amal, 

thanks for you valueable input. 

Indeed, the differences between PCs that regularly have the issues and PCs that never experienced it, is a Myriad font shortcut under C:\Windows\Fonts. 

We will now remove the Myriad font shortcut from all PCs and will flush the Local app data cache afterwards. 

Then time will show if this is a sustainable solution or if we see the issue again. 

I will keep you posted. 

Best regards, 

Martina

[Amal.]

Hi Martina,

Hope you are doing well.

Please confirm if you are still experiencing the issue after applying the steps shared above?

Regards

Amal

[Martina23762383dfd2]

Hi Amal, 

after extensive testing I can confirm that the deletion of the Myriad font link togehter with the Adobe cache prevented the problem to occure again. 

Thank you so much for your support!