Please check your avast5.ini file and see if this option will help you
1. Avast main GUI -> settings -> troubleshooting -> disable the self defense module and save settings (don't worry about the messages, accept).
2. search for the file "avast5.ini" (even if it is version 7 of avast); EDIT the file with notepad. On Windows XP, the file is located in C:\Documents and Settings\All Users\Application Data\AVAST Software\Avast
On Windows Vista and 7, I am not sure but it should usually be in C:\ProgramData\AVAST Software\Avast
3. in "avast5.ini", look for the "[common]" section. There should be an entry named "ShowSetupOutro".
4. change the above entry "ShowSetupOutro" from 1 to 0 (zero).
5. save the file and reboot.
6. go back to avast main GUI -> settings -> troubleshooting -> enable the self defense module and save.