Today's viruses, worms, and Trojans often target your first line of defense, disabling your antivirus software and modifying the HOSTS file to prevent access to your antivirus vendor's website. And these same threats often block access to the Registry and Task Manager, making manual removal all the more difficult. Fortunately, with a little foresight, you can stymie these attempts to gain illicit control of your computer.
FRISK Software, one of the oldest and most venerable antivirus vendors, provides F-Prot for DOS free to home users. And though it's designed for DOS, you can run it commandline in Windows XP too. There's even an interactive mode that makes it a bit easier for those not used to working commandline.
Obviously, if viruses can disable running antivirus software, it would be trivial for the same virus to delete your F-Prot files. For this reason, keep your copy of F-Prot on CD. This will mean periodically burning a new F-Prot CD to keep the definition files current, but the price of a CD is cheap protection.
Follow these tips to keep an up-to-date copy of F-Prot available at all times:
- Download F-Prot for DOS:
- Download both sets of virus signature files offered on the signature update page located at http://www.f-prot.com/download/signaturefiles.html.
- Create a directory named F-Prot
- Extract the downloaded f-prot.zip file to the newly created F-Prot directory.
- After you've extracted f-prot.zip, extract the fp-def.zip and macrdef2.zip to that same directory. IMPORTANT: Do not do this step out of order. If you extract the def files first, the newer ones will be overwritten when you extract the F-Prot program.
- Burn these files to CD.
- Repeat this process periodically to ensure you always have the latest version of F-Prot for DOS and the latest definition files on hand.
- If you've already become infected, use a different computer to follow the steps above.
Now that you've got an up-to-date copy of F-Prot for DOS, here's how to use it.
- Insert your F-Prot CD into the CD drive.
- Boot the system using a clean rescue (boot) disk or boot into Safe Mode with Command Prompt. (See How to Boot into Safe Mode http://antivirus.about.com/od/securitytips/ht/safemode.htm)
- Once you're at the command prompt, switch to the CD drive (in most cases, this will be the D: drive, so type D: and press enter).
- To run F-Prot in interactive mode, type:
- Press enter. Use the arrow keys on the keyboard to manuever through the options and scan the PC.
- If you prefer to run F-Prot commandline, type
- Press enter. This will display a list of available commandline switches.
Remember, an ounce of prevention is worth a pound of cure. The time to make that F-Prot CD is now. Follow the steps outlined above to make the CD then practice using that CD. Doing so will ensure that both the protection (the F-Prot CD) and the protector (YOU) are ready when disaster strikes.