HARDWARE: HITACHI Travelstar from thinkpad 41. (newegg.com/product/product.aspx?Item=N82E16822146042) SYMPTOMS: Knocking; No operating system found. ================================================================ OVERVIEW: Apparently, the machine was dropped, resulting in the following error upon booting: "Windows could not start because the following file is missing or corrupt: <windows root>\system32\ntoskrnl.exe After expanding the file from an XP installation disk, I ran chkdks /r and it said there were errors that couldn't be fixed and the HDD started knocking. It knocks at a rate of 1 knock/sec. I restarted the machine and it says there's no OS and the knocking continues. ================================================================ Some guy told me to dl and run download the IBM - Hitachi Drive Fitness Test and another guy told me to pop it in an external enclosure, but aren't both of those options pointless if the drive is knocking? Doesn't that mean the drive head is toast? If yes, how do I fix the drive head, or...? Thanks. P.S. I can operate a soldering iron if need be.