Not all infections can be cleaned, e.g. where the complete content of the file is malicious, like a trojan, only true virus infections can be cleaned and then only if the infected file is covered by the VRDB.

The fact that you get a pop-up saying the file can’t be found means that there is a registry entry trying to run it on boot and fails (great). Run HJT and you should see the entry for this, tick the Fix box to the left of it and click the Fix Selected button at the bottom of the HJT window.

Program & Tutorial - Also useful as a diagnostic tool - FileHippo Download - HiJackThis - HJT Information HiJackThis Tutorial.