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Windows 7: Master Boot Record (or partial) on seperate HDD

26 Jun 2012   #1

Windows 8 Professional
Master Boot Record (or partial) on seperate HDD

Ok, so three months ago a customer contacted us saying that her emachine was freezing. A technician evaluated the machine and concluded via process of elimination (minus an actual HDD test) that the freezing was due to HDD failure, as it was the only thing left. The customer didn't want to pay us to transfer her data to a new drive, so she did it herself. Upon completing the data transfer, she then physically disconnected the old SATA drive, which then resulted in Windows taking a dump and screaming about a boot medium. Long story short: The previous tech told her that she would be able to transfer her data, disconnect the old (failing) HDD and move on with her life, and this did not turn out to be the case.

The machine was brought back yesterday, roughly four months later (She hasn't had any freezing issues since the other tech assessed it) wanting it set the way she was promised.

My assessment concludes: Both HDD's (new and old) were present in the system at the time the fresh Win7 install was performed on the new HDD. For some reason, 7 stuck at least part of the MBR on the old HDD, creating a dependency on the presence of the old drive in order to boot at all.

I used a Win7 repair disc to repair the MBR on the new drive so that the old one could be removed. The box that should have presented at least one OS to select and perform the repair on was empty. The only other option at that point is to point the application to the driver for the HDD so that it can load the OS. I pointed to the HDD driver using the direct file path, and it was treated as though it was an empty file (and it wasn't).

I attempted dong the repair manually from CMD (on the repair disc). From CMD, "bootrec \RebuildBcd", which located every present installation of Win7 (both HDD's have a copy) The utility prompted me to choose either or all installations followed by a confirmation (Y/N). After selecting "Y" and pressing "ENTER", it goes to town and takes another dump (nothing happens).

Finally, I downloaded EasyBCD 2.1.2, used it to recognize EVERY boot record, deleted the MBR on the old HDD, and rebooted.

Now, the system boots straight to the new HDD without prompt from bootloader (which is good) but still requires the presence of the old HDD (I disconnected it, alas...)

In the end: I called and told the customer that "I'd be happy to GHOST all her data and slap a fresh Win7 install on the new HDD (with a fresh/whole MBR) and then drop all her data back onto it. However, this would require more time; the other option being that she accepts the machine for what it is, perfectly functional minus the dependency on the old HDD."

Typically, I wouldn't have considered this option, but I found ZERO indication of the old HDD failing, other than "BAD" written on the drive with Sharpie. The customer was happy yesterday and accepted the current state (she didn't want to invest more time/money into it) but today when she picks it up she isn't happy because she was told four months ago that the drive was bad and now I'm saying I don't see an indication of it.

Anyone have a solid solution for this? Other than pulling the data, installing fresh OS, then dropping data back on; or not installing OS with two drives present in the first place

Why would Windows do this at the presence of two drives in the first place??


My System SpecsSystem Spec
26 Jun 2012   #2
Microsoft MVP


Unplug the old HD, set WIn7 HD first to boot in BIOS setup, Mark Win7 Partition Active then run Startup Repair - Run 3 Separate Times until Win7 starts and has it's own System Active flags.

If the Win7 partition is incorrectly Logical then it must be converted first to Primary before it will mark Active. How to set partition as Primary or Logical.

If this fails boot free Partition Wizard to confirm the Active flag is on Win7, click on Disk # to highlight Win7 HD, from Disk tab select Rebuild MBR, Apply.Partition Wizard Rebuild MBR Video Help. If WIn7 doesn't start then run the 3 Repairs again.

If it won't write the System boot files to Win7 it may be corrupted from previous attempts. As a last resort try shrinking C from the left by 200mb using Partition Wizard boot disk to create a Primary NTFS partition marked Active, then run the 3 Repairs to create a new System Reserved boot partition. Partition Wizard Move/Resize Partition Video Help.
Partition Wizard Create Partition Video Help
My System SpecsSystem Spec
26 Jun 2012   #3

Windows 8 Professional

The machine has been out the door since this morning; so I'm just looking for the "why?" at this point. Thanks for the information though; I didn't think about using third party software to mod the active/logic configuration. Do you think The Win7 install skipped the MBR because it identified one already on the first HDD?
My System SpecsSystem Spec

26 Jun 2012   #4
Microsoft MVP


Yes, the installer writes the System boot files to the first Active partition or the first partition on the first HD. It happens frequently when other hD"s are not unplugged during install. We have seen it countless thousands of times here.

You must mark the Win7 partition Active for repairs to identify the target location to repair or rewrite the System boot files.

The only instance where unplugging the other HD, marking Active then running Startup Repair x3 fails is when other fixes have been tried that corrupt Win7 boot files beyond repair. In this case sometimes constructing the System Reserved partition as suggested will work. You need a clean slate to write the boot files to override the mess made on Win7 part and rebuild the MBR.
My System SpecsSystem Spec
26 Jun 2012   #5

Windows 8 Professional

You'd think, logically, Windows would either want to do a full install on the new drive, or stripe across both like a raid 0. This particular configuration seems highly impractical for a default action. It must have something to do with with two MBR's being in too close a proximity.

Thanks for the confirmation and the feedback, gregrocker!
My System SpecsSystem Spec

 Master Boot Record (or partial) on seperate HDD

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