Do virus scanners automatically do both hard drives?

[LightSpectra]

I use Spyware Blaster, AVG, Spybot and Ad-Aware. Do they only scan the drive they are installed on, or do they do both of the ones on my computer?

 

[Genocidicbunny]

i know avast has an option to scan all drives ( inc. removable media ). not sure about the ones you listed though. Id look for scan options, if they do have the option to scan both HDD's, it would be in there.

 

[Macha]

By default they scan all internal drives. There is a setting to scan flash drives and USB hard drives aswell.