In # 9 you asked about the possible registry hack. I think this is what you are referring to:
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base: 322756 (How to back up and restore the registry in Windows XP )
How to back up and restore the registry in Windows
To resolve this issue yourself, enable the AHCI driver in the registry before you change the SATA mode of the boot drive. To do this, follow these steps:
Exit all Windows-based programs.
Click Start, type regedit in the Start Search box, and then press ENTER.
If you receive the User Account Control dialog box, click Continue.
Locate and then click one of the following registry subkeys: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci
Thanks Greg, PW says "Failed to find Windows directory" so 'check file system' is greyed out, but PW's partition explorer shows the windows system files right there!
Also I'm getting "The selected partition does not contain boot.ini file"
In Win7 Startup Repair is run from the Desktop. For this reason Startup Repair contains multitude tests to check all parameters, making it necessary to sometimes run Startup Repair - Run up to 3 Separate Times . During this process it should repair/rewrite the System boot files unless something is blocking it from doing so.
Was another HDD removed that may have been providing the System boot for this Win7? If so you might try copying the 64bit Win7 boot files into the partition if 3 Repairs fail to boot it. I'm on my 32 bit laptop right now so I can't upload them but you can copy them out of any 64bit System partition after unhiding Hidden and System Files in Control Panel>Folder Options>View.
I noticed there was no System reserved partition on the drive so I made one and copied the contents over from a fresh win7 install along with the windows boot folder, then I ran the system recovery options again but it still wouldn't start. So then I ran all the BootRec commands listed here http://support.microsoft.com/kb/927392http://support.microsoft.com/kb/927392 and Viola! She started
Constructing a System Reserved works once we know a Win7 partition cannot be made bootable. It would have been suggested if you'd reported back failure on all other steps. The bootrec commands also can sometimes work when run manually when their automated run from Startup Repair doesn't work.
These are steps given along with everything else that can be done for Troubleshooting Windows 7 Failure to Start. The only reason I held off giving them to you is because this was supposedly triggered by a BIOS Upgrade which almost always means a BIOS setting slipped. We needed to rule that out and then try the OS repair basics before dumping a bunch more steps in the hopper.