If you did a full wipe of the hard drive reformatted and then reinstalled you should be OK. If you want to be abosultely certain and do it again.
The best proceedure is a low level format. This completely wipes the drive. Then reinstall the OS.
Use the free version of Active@ KillDisk
Or Darik's Boot And Nuke
Did you scan the external also?
2 guidelines/rules when backing up
1) Backup all your important data files, pictures, music, work etc... and save it onto an external hard-drive. These files usually include .doc, .txt, .mp3, .jpg etc...
2) Do not backup any executables files or any window files. These include .exe's, .scr, .com, .pif etc... as they may contain traces of malware. Also, .html or .htm files that are webpages should also be avoided.
Edited by boopme, 04 May 2009 - 03:12 PM.