Help with a Tricky Trojan

A scheduled scan found the following threat:

Threat: Win32:Hupigon-ONX [Trj]
Location: C:\ProgramData\Microsoft\search\data\applications\windows\tmp.edb

Avast failed in trying to move it to the virus chest. The program suggested a boot time scan, which I performed. The boot scan did not find the threat however. After the boot time scan I pulled up the previous scan log that found the virus, and tried to move the threat to the chest again, and got the following error: Error: Access is Denied(5)

Not sure where to go from here. The file is in the location above, but I cannot delete it (says its in use by another program).

Any suggestions? Thanks in advance.

follow the guide and attach the logs. http://forum.avast.com/index.php?topic=53253.0