Virus Problem

[dkchew]

It appears that there is a virus in my Windows 98 PC system.

The system reports a non-valid system disk and does not allow me to start the computer. I used my start up disk to get the DOS prompt. Checking the C: drive, I see that all the directories have been wiped out and replaced with files (5 in my case) named with 2 letter symbols. The C: drive has also been re-labelled #;<.

Can someone please help me with:
1. what is this virus,
2. how it can be removed without erasing all my data.

My system has Grisoft's AVG program installed.

[WhatsThisBoxFor?]

If you can only see 5 files in DOS then you are probably in trouble. Was AVG up to date? Have you downloaded anything recently? I couldn't find anything on google, sorry. What are the names of the files?

[dkchew]

Unfortunately, I know I am.

AVG was up to date through July 19, 2004.

The names of the files were all in the form of symbols. For example two of them were named 0$.


Regards.

[ghost2003]

You could try f-prot for dos to scan for viruses in dos but I doubt it going to be any good if you can only see 5 files. If it doesnt help then youll need to reformat. But maybe you could try a recovery program to try to get some of your files back if you really need them but I wouldnt count on that.
http://www.f-prot.com/products/home_use/dos/

[GaryRouth]

My first guess would be some sort of boot virus. Some are more destructive than others. If you are lucky, this one hasn’t killed the data on the drive, but has infected the MBR (Master Boot Record section of your hard disk – which would be why you are seeing the “invalid disk” errors). Sometimes a cure is the fdisk/mbr command –if the system is booted from a clean, write-protected floppy. Some boot sector viruses will infect any diskette that is not write-protected upon access. I like ghost's idea for using F-Prot. You could also I try slaving the drive in a well-protected system. Make sure it’s the slave, or the Helper PC will be infected also.

If you’re unlucky, the data has been damaged already, and you may need a Data Recovery tool. [there are several such tools over at download.com]

mskb article
http://support.microsoft.com/default...b;EN-US;128730

sophos article about boot sector virus
http://www.sophos.com/virusinfo/analyses/anticmos.html
sophos solutions for such cases
http://www.sophos.com/support/disinfection/mbrnvir.html

Hope it’s one of the more benign infections, and you’re OK again soon.
. . . Gary