C:\WINDOWS\system32\tmp0_132689667778.bk TROJAN FOUND. I DELETE IT EVERY TIME BUT IT COMES AGAIN AND AGAIN. CAN’T AVAST FIND THE ROOT OF THIS PROBLEM?
Please check the generic cleaning procedure here:
http://forum.avast.com/index.php?topic=34545.msg289783#msg289783
Welcome to the forums, eayan. 
If you are still having problems after following Tech’s suggestion above, please post back in this thread again.