Formatting good enough to get rid of viruses?

[glorygeek]

I was re-installing Windows for a customer that fell for a phone tech support scam (the scammer had control for quite a while). I was unable to run antivirus scans (on multiple programs, including Malwarebytes Chameleon, it said unable to scan after starting), but had no other visible solutions. After seeing the customer had little personal files or programs installed, I decided a re-install of Windows was the way to go. I started a drive wipe out of an overabundance of caution, but after seeing it would take 12 hours, decided it was not worth the time as well as the wear and tear on the drive. I re-installed Windows and gave the computer back to the customer (and scanned it both with Malwarebytes and Panda to ensure no viruses had been transferred), but have been worried of a boot sector virus that may have remained after a reformat. Is this a valid concern?

 

[Paul NZ]

Doubt they'll have the brains to put a boot virus on it

Dont think any of them put viruses on a system anyway. They just disable things and expect you to pay for it later

 

[Jim_and_Evil]

If they haven't came back to you with further issues as of yet, Id say they got lucky... Compared to what I had to go through with fixing a friends laptop that had a malicious installer that fcked everything (linky http/www.tomshardware.com/answers/id-2409870/sisters-friend-weird-virus.html)

 

[lynx961]

Formatting a computer is the best solution if you have a virus you cant remove it or afraid of things it left or damaged.

When you format chose to delete existing partition and repartition your HD and format.

Make sure you disable system-restore point in windows because if there is a virus it save itself with restore point and it come back.

Install Antivirus because the key of a clean computer is a good antivirus, Whatever you do if you don't protect your computer with antivirus virus will come back again.

Scan every removable drives you have and virus will not come back.

Not all antiviruses are good, For me i use kaspersky because it cleaned my computer from viruses that Norton didn't detect and this virus damaged my work files.

After that no concern for virus to come back because the antivirus is preventing it, and i dont think any virus will comeback from a formatted HD.

Im using this method from 10 years and no virus come back with me from a HD i formated it.

 

[Skylyne]

First off, I'd only recommend formatting as a last ditch effort to clean your PC. Since most viruses can be removed relatively easily, and few of them really root themselves deep, it's best to just do it by hand; it also gives you a much better look at what is currently infecting computers.

On the other hand, a reformat is typically enough to prevent the customer from having any more issues. Doing a drive wipe is always worth it, if you genuinely think the virus may survive the reformatting and re-partitioning. While the virus shouldn't be able to remain persistent, why not wipe it any way? Wiping is a much more secure form of cleaning the drive, so you might as well do it.

If the virus did manage to infect a boot sector, a full wipe is in order, and a format (depending on how it's done) may not be enough to wipe it out. If there is no complaint from the customer yet, then the reformatting most likely did the job. You might want to contact the customer, though, and ask to see the computer (free of charge, of course) to tell them you'd like to double check your work. While some people might feel a bit worried, reassurance that you're simply trying to make sure they are safe, and that you completed the job is something that is kind of rare, yet quite nice. Depending on the customer, they might be quite taken by the suggestion, and find it more of a positive move on your part. It's an option to consider.