I am using Acrobat 8.20 under Windows XP Professional version 5.1.2600, which is the lastest service pack plus various security upgrades.
Under Acrobat 8.00 I could add a digital signature to a document and save it with the original filename without problems. Some time about when I upgraded to Acrobat 8.1? the process no longer worked. When I tried to save the file Acrobat hung and I have to shut it down using the Task Manager. When I restart Acrobat and open the file the digital signature is there but is marked as invalid. Usually, but not always, I can clear the digital signature and then resign, and save the document without problems.
I have done an Acrobat installation repair but that did not fix the problem.
Apart from upgrading to Acrobat 8.20 the only change I have made to Acrobat is to add the TerraGo addin.
Any ideas on what or where to look for a solution, or how to fix the problem?
Thanks in advance,