I would guess that trying to run too many anti-malware/anti-virus programs is counter-productive as they would interfere with each other, particularly if they are set to do some form of real-time scanning (or whatever the techical jargon is for that). Currently I use MWB Pro and Norton (Anti-virus). However as no program is "perfect" is there any benefit to using say Malwarebytes Pro as the main form of protection against malware and then using a second program (not with real time scanning) to perform intermittent additional scans? Thanks Dave PS OS Windows 7 Professional (64bit) on home PC