Acrobat 9.0 - "Failed to connect to a DDE Server"

I have Comodo Internet Security 4.1.150349.920 – just upgraded. Running Windows XP SP3.

The new version of Comodo seems to have caused a problem with Adobe Acrobat 9.0. When I try to open a PDF by double-clicking it, it does not open. Then after some time (several minutes) I get a dialog box “Fatal Error - Acrobat failed to connect to a DDE server.”

When I check the Defense+ event log, I see a lot of events where Acrobat.exe tried to send a message to Acrobat.exe. Is that where the problem is occuring?

I have listed Acrobat.exe as a trusted application, etc. everywhere I can in Comodo, but this still happens.

Any ideas?

THanks.

Can you show a screenshot of the logs?