one last note: there are a few viruses that install themselves in the master boot record, and a standard reformat does not kill them. in this case I believe that you need a decent virus program to detect it (so that you will know if you have deleted it when you rescan), then you may have to do a low level format, and then run the scanner again to see if it was sucessfully removed. The problem with the master boot record virus would explain why you could be reformatting and still getting your virus back. low level formatting is simple, most drives come with a floppy that contains the instructions and the format utility.