Emails with attachments are blank...

Hello,

since I changed from Avast 4.8 Prof. to Avast Internet Security 5 I get blank emails without attachments. Normal emails, without anything attached, are displayed correctly. This occurs in my CRM-Program (TMbusiness2009). It works with an integrated chilikat-mail-software. The headline in the program shows the right naming of the email and that there’s something attached. But as i said, when opening everything is blank.
The same Emails received in Thunderbird are displayed quite right!!!
Some ideas out there?
…would be nice…
Thank you…
luddi