It is possible for a failing hard drive to produce file corruption. When you say that the drive was wiped before reloading windows, did you use the hard drive manufacturer's utility for doing this? I believe that some of these will check for bad sectors as they go and take them out of service (perhaps even bringing new sectors online, if there was some unused slack in the drive). In any case, it would be a good idea to run a thorough disk scan, using the hard drive manufacturer's utility before you reinstall your operating system on that drive again. (Zeroing out the drive, using the manufacturer's utility, should overwrite any virus that might have been on the drive previously.) It might also be a good idea to try and rule out a couple of other sources of data corruption before you do this. You can download and run either MemTest86 or Microsoft's Memory Testing Utility in order to make sure that your RAM is working properly (let these tests run for several hours, not just one pass, unless they are already finding a problem). You might also want to make sure that your processor isn't getting flakey. The number crunching distributed client for the Prime95 project is commonly used for this. Run the torture test for several hours to make sure that your system isn't misfiring. (I advise making sure that your fans are working and the CPU heatsink is not clogged with dust before running Prime95 because it will heat up your processor through heavy usage.) A failing hard drive controller on the motherboard can also cause data corruption. I don't know of a good test for checking this other than copying and moving a very large file (several hundred MBs) from one location to another on your harddrive. You can use the ability of compression programs, like WinZip, to produce a CRC number for the file to make sure that it isn't being corrupted after you've moved it around several times (i.e., when you zip the file you should get the same CRC number after its been moved a few times as you did before hand; many compression programs test the integrity of the contents of a zipped file, so you can use this feature after moving a zipped archive around, too). I hope some of these ideas are helpful. John Sproule ----- Original Message ----- From: "Gordon Totty" <[log in to unmask]> To: <[log in to unmask]> Sent: Sunday, January 01, 2006 12:41 AM Subject: [PCBUILD] System File Corruption > This is sort of a theoretical question. System files on a computer are > repeatedly getting corrupted in spite of extra care with virus detection, > reloading from clean sources, etc. The HDD has been wiped and reloaded, > but the problem returns rather quickly. Two questions: > > Is it possible for a virus to exist in the normally inaccessible HDD > manufacturer's space on the HDD? > > Is it possible for failing HDD to produce these symptoms? The NOSPIN Group has added a new feature on our website, web based bulletinboard for questions and answers: Visit our sister website at http://nospin.com