Bitdefender found Thousands of I/O errors in file system.

Firstly, some of those infected files may not be true.
Some anti-virus software do not like other anti-virus software, so it is marked as infected.
And there is some difference between free or paid version.

For me, i am using SuperAntiSpyware free edition, meaning not active.
I do run this SuperAntiSpyware after surfing, almost daily.
Before running, this software do have updates daily, which some do not.
There are options for, quick scan, full scan. But since i run daily, then do a quick scan.
Although i do have a active a Panda Internet Security but not able to do a better job then this SuperAntiSpyware.
So i decide to buy the active version.
I did use this to scan my friend laptop, and did found a lot of nonsense virus, malware, etc.

If you do a clean install, there is no need to do scan for virus, malware, etc.
If not, do a FULL Format, which may take hours depend on the HDD size.

Thanks for the reply. Actually, I did a full format. It took like 6 1/2 hours and it deleted the MBR. Thing is... I just reinstalled Windows and I don't have any other antivirus or antispyware program running actively on my system atm (I haven't connected to the internet yet because I'm a bit paranoid). The only thing I have installed is Malwarebytes free version (I did an offline scan).

I read that the Bitdefender Rescue CD may not be able to scan operating system files, files in use and user-protected files. Maybe the 7k (or so) files are either OS system files, in use or protected.

I will scan the PC with SuperAntiSpyware and I'll keep you in touch.

SuperAntiSPyware found nothing.

Those are the files (a portion of them) that can't be scanned. You must open the file with Notepad++.

Devadip said:

The only thing that bothers me is the high number of I/O errors found by the Bitdefender Rescue CD scanner. When I scan the "File System" directory, I get a couple thousand I/O errors and Bitdefender is telling me that it can't scan these specific files. It also says "Threats may be present on your system".

I/O errors have nothing to do with antiviruses or infections or anything related to security. It means that the HD is failing to function as it should, and the AV has no clue what's going on there (it cannot conclude that it's clean, but neither confirm an infection), it's not its business to deal with disk errors, but instead give chkdsk a try beforehand. If those I/O problems are real, it's quite possible that the disk is failing and needing a replacement, virus or not.

However, you should never trust anything if you're running a compromised machine. Those scans are only useful if they're running from an external OS, not the broken one. A rootkit can for sure hide itself by throwing fake I/O errors to disguise itself, so if you're running the infected OS, forget about those results. Booting with a CD, or putting the HD as a slave on another computer is fine though.

Devadip said:

I scanned the PC before formatting it.

There is no point in doing so, if you know the computer is infected. If you're formatting, everything will go away, viruses included . Anything found will no longer be there. Curiosity is the only use of a previous scan.

Devadip said:

From what I know, it writes zeros on the disk and it acts like a secure erase if i'm not mistaken.

No! This is terribly wrong. Diskpart sole purpose is to manage partition tables and a few special system tables, but nothing else. All a full clean really does is to delete the full partition table, leaving the rest alone (you can realize that based on that it's lightning fast command, while filling everything with zeros would take hours). It's not documented and not meant to do otherwise, and in fact, it's quite easy to undo a diskpart clean once you know its tricks.
I find it disturbing that for the last days the forum seems to be spreading such a myth.

Note that, however, while all the data is intact, the OS has no clue on how to use it, as the main indexes describing its meaning are lost. That's why it's so dangerous and issuing it is almost equal to all data being lost.

Devadip said:

Is it safe to connect the PC to my network after using Windows diskpart clean all?

Once you've reinstalled a clean OS, it's just like a new machine. Everything that was previously there is gone, and I find safe to assume that the computer is clean, no matter how bad was before.

Devadip said:

I doubt that malware could've survive the diskpart clean all except if I'm dealing with a pretty mean rootkit.

Technically, everything survives a diskpart clean But in practice no, nothing remains, no matter how nasty the virus was. And no, not even the meanest of rootkits can survive a reformat. Reason is simple, you boot another OS to blow the infected thing up. At that point, no software in the affected computer runs, including malware, so it has no chance to lie to you. If you reformated using a safe computer, it's safe to assume that all is clean now. Typically you reformat using the Windows install CD, which if downloaded and stored in safe locations, is reasonable to trust in it.

I see. Thanks for the information! I did a chkdsk and there were no problems whatsoever. I also tested the WD drive with WD WinDLG and there were no errors.

Maybe it's just me, but when I saw this post talking about diskpart, I didn't quite get the difference between diskpart clean all and secure erase because of the way it was written (and I didn't know what secure erase was). "You could use the clean all command (secure erase) to do the above and also have each and every disk sector on the HDD written over and zeroed out completely to securely delete all data on the disk to help prevent the data from being able to be recovered."

It's an excellent guide, but it's just the "secure erase" hyperlink that got me confused the first time I saw this tutorial. I get it now though. Sorry for my ignorance.

I will install Windows on the formatted drive for now because my friend is coming back in two days and he want to be able to use his PC. He has to leave town every sunday for work so he'll probably want to play some games during his 2 days off.

If the HDD is failing, I'll tell him to get an SSD I guess. There won't be any personal files on the HDD anyways. He's planning on buying an SSD soon.

I installed the missing drivers and I scanned with ESET Online Scanner. Nothing was found. Everything is fine. Thanks for your time and help.