I can't get rid of "Whale-9" Worm

[juanymerja]

Avast scanner found a worm in my pc, named "whale-9", but avast is unable to remove it to the chest or delet it.  I think the worm release a false directory address.  So everytime I try moving the worm to the chest or delet it, avast gives a message error, and it says the peration faliled or something like that.
If someone can help me, I'll be very grateful.
Thanks a lot!

[DavidR]

What is your OS ?
What is the infected file name, where was it found e.g. (C:\windows\system32\infected-file-name.xxx) ?

Deletion isn't really a good first option (you have none left), 'first do no harm' don't delete, send virus to the chest and investigate.

Windows in its infinite wisdom protects files in use (even malware) or in system folders, so it is likely that avast! can't delete or move files in use. So schedule boot-time scan in avast's menu if you have XP, win2k or NT, otherwise boot into safe mode and run an avast scan. This should ensure that the file isn't in use and avast should be able to deal with it.