It appears that sometimes, Chkdsk makes things on the HDD worse! So if you need to recover data, please use another utility! But, installing the wrong IDE or SCSI driver (not for your chipset) can cause the symptoms you have. Chkdsk probably would only make things worse in that case! A long story, but I had an incident in July, 2003 reguarding my Asus A7N266-VM/AA motherboard, which was my newest DIY PC build at that time. Shame on you, Nvidia, you wasn't straight! Didn't warn me that the IDE driver is for nForce2 only! The Asus A7N266-VM/AA is nForce 1-based. After installing that IDE driver, on reboot, Windows crashed with STOP: 0x0000007B INACCESSABLE_BOOT_DEVICE then after I rebooted, Chkdsk ran and it reported orphaned files then I couldn't stop it! Afterwards, I discovered that random files were gone, some recent pictures and AVI files taken with my Creative PC Cam 300 were gone!