Explorer triggers "Malicious URL Blocked" alarm + IMAP not working

[prgabor]

I have updated to Avast! V7 on 2 PC's: one running on Windows7 the other on XP.
On both PC's when starting an Internet browsing session (Explorer or Firefox) I am getting following alert message:
Malicious URL blocked!
Object: http:/
Infection: URL Mal

In addition to this, my IMAP server stops working and I cannot start Outlook 2010.

The Internet can be used in spite of the URL blocked message. I have played around a lot with the URL problem. It seems, that it is somehow connected to my Gmail account. There is no alarm if I am logged out. Logging in reactivates the alarm, but Gmail comes up and seems to operate perfectly.

Does anybody have this problem? What is the remedy?

[Pondus]

Malicious URL blocked!
Object: http:/ 
Infection: URL Mal

what is the Object URL ?    post it non clickable

On both PC's when starting an Internet browsing session (Explorer or Firefox) I am getting following alert message:

start with one computer

follow the guide here and attach the logs from MBAM / OTL / aswMBR
http://forum.avast.com/index.php?topic=53253.0

then one of the trained malware removers will help you