|Disconnect all USB devices that have any memory including HD, flash drives, cell phones, SD hubs, etc., remove any CD/DVD's from the drive, and anything that might be bootable. Then go into BIOS set up and look for the hard drive. If it is recognized, make sure it is bootable and in the boot order just behind the DVD drive. If the drive is not recognized, it is probably bad but check all connectors and try different ones If the drive is recognized but still not bootable then boot to DOS version of Seatools from Seagate and do the short test. If the drive is good then you may be able to repair the installation, In Windows 7 (and also on Windows 8.0 only) a Repair Disk can perform a Start Up Repair which will fix the boot sector and get you up again. On Windows 8.1 I believe there are some repair tools accessible from F8 that may help you. For most OS' an install Disk is bootable and contains repair tools that should help.|
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You have to be a little bit crazy to keep you from going insane.