BleepingComputer.com: i think ihave virus/trojans

one day i got a mass virus load, it shut down my antivirus and other applications so i had to do a reformat.

After the reformat my harddrive seemed clean, but my concerns was my external HDD which was connected to my PC at the time the viruses arrived.

However, i scanned it with Avast, Superantispyware, Spybot and Blacklight, only thing they found was an old GTA IV crack (but that was probably a false positive)

I guess this isnt a lot of info but should i access my external? Or should i use more programs to scan it? (suggestions please)

I dont want to reformat it since i got lots of stuff i dont want to lose.

If its any help i had some Win32/heur on my main drive before i reformat it.

If you reformatted, you should be clean

Please download
Flash_Disinfector.exe by sUBs and save it to your desktop.

• Double-click Flash_Disinfector.exe to run it and follow any prompts that may appear.
  
• The utility may ask you to insert your flash drive and/or other removable drives. Please do so and allow the utility to clean up those drives as well.
  
• Hold down the Shift key when inserting the drive until Windows detects it to keep autorun.inf from executing if it is present.
  
• Wait until it has finished scanning and then exit the program.
  
• Reboot your computer when done.

Note: As part of its routine, Flash_Disinfector will create a hidden folder named autorun.inf in each partition and every USB drive that was plugged in when you ran it. Do not delete this folder...it will help protect your drives from future infection by keeping the autorun file from being installed on the root drive and running other malicious files.


What it does:

The vaccination is two fold. If the computer's autorun settings are enabled, then files can spread to any drive that's plugged in. If the drives themselves are vaccinated, all the tool does is prevent the autorun.inf file from executing any of the malicious content that may have been copied to the drive when it's plugged in.

In other words, say you vaccinate your USB drive. The tool writes an autorun.inf file that's harmless. When it's inserted in a computer that does not have autorun disabled, the computer will attempt to read and process the autorun.inf file from the inserted drive. If an infection that spreads to network or USB drives is present on the computer, the infection may very well succeed in putting the files on the drive, but they will not be able to overwrite the autorun.inf file and as such the files will not run without user input (i.e. actually clicking on them).

If the computer's infected and that infection tries to multiply to external drives, then yes, it'll likely copy some files to it. You could then remove those as they wouldn't be running automatically once the drive's inserted in another PC. Nothing you do will stop files from being copied over to an external drive if an infection of that type is present on the system. Well, technically you can prevent that by setting the write protect mode, but not every USB drive has one of those and it prevents writing anything to the drive.