Depending on what was done and when, it appears with so many OS's installed, the boot manager has been confused. Evidently the 750Gb drive has an entry in the startup string that is in error. If the OS installed on the other drives is good, why have Windows 7 installed again on the 750Gb drive? Use the 750Gb drive for data only. In order to fix this, the OS needs to be directed to look on one of the other drives. Start by looking at the BIOS settings with the 750Gb drive attached. See which drive is selected for first boot device. If it is the 750Gb, change it to another and then try reboot. If it still persists on boot failure, then remove the Boot loader info from the 750Gb drive. Caution is advised, however. If a mistake is made in one of the other drives instead of the 750Gb, then it may not boot at all.
EasyBCD may be of some value in this. Problem is, the computer has to be running to get it installed.
http://download.cnet.com/EasyBCD/3000-2094_4-10556865.html
I think some planning and an external enclosure for the 750Gb drive may be helpful.
Ok, so i noticed a few weeks ago the computer downstairs would not boot up (hardly use it, but important data on it), didn't worry about it because i figured it would be a simple fix. However i been working on it for days now with no fix.
I have 3 hard drives in this machine, 2 IDE 80gb and one 750gb SATA drive. One of the 80gb drives runs windows 7 while the other has windows 8 installed. My 750gb has windows 7 installed.
When i unplug the 750 gb hard drive , the other 2 work perfect, no problems, but when it is pluged in, i cant load ANY operating system from any of the hard drives. So i can't even boot up either of my 80gb hard drives so i can access my files on the 750gb hard drive. This all holds true with any of my bootable usb sticks. they work fine when the 750gb hd is unpluged, but as soon as i plug it in my usb drives do not boot up. So obviously their is a problem with the 750gb hd.
When i try to load a operating system WITH the 750gb hd pluged in, the operating systems start to load and get hung up (locked up). If i ONLY have the 750gb drive hooked up, and insert my win7 recovery disc , it loads the files then starts the boot up process and again gets hung up. I cant even install a clean install of win7 if i wanted too.
Any suggestions? i really need the data on the 750gb drive.

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