Lost MBR

[comdude85]

Hi all,
I've been running 7 Professional for a couple of weeks now, and all of a sudden it won't boot. All I've done is install a new hard drive as a data drive, and when I power up I get "DISK BOOT FAILURE, INSERT SYSTEM DISK AND PRESS ENTER". (Yes, the OS drive is still installed, see below). I've inserted the 7 install disc and tried several different repair suggestions I found online, including using the UI Startup Repair tool (which has, on 3 subsequent boots, claimed to have identified and repaired the same issue of no system partition found) and various command prompt methods. The installer will not acknowledge that I have any OS installed, but it will happily let me access the OS drive as C: via a command prompt. This is a bit of an emergency, is there some command to just create a new MBR?

 

[Bare Foot Kid]

Hello comdude85, welcome to Seven Forums!


When you added the second HDD did you move the SATA connector cable for the original HDD, if so put it back like it was?

 

[comdude85]

Nope, didn't move the original one.

 

[SquonkSC]

Hi all,
I've been running 7 Professional for a couple of weeks now, and all of a sudden it won't boot. All I've done is install a new hard drive as a data drive, and when I power up I get "DISK BOOT FAILURE, INSERT SYSTEM DISK AND PRESS ENTER". (Yes, the OS drive is still installed, see below). I've inserted the 7 install disc and tried several different repair suggestions I found online, including using the UI Startup Repair tool (which has, on 3 subsequent boots, claimed to have identified and repaired the same issue of no system partition found) and various command prompt methods. The installer will not acknowledge that I have any OS installed, but it will happily let me access the OS drive as C: via a command prompt. This is a bit of an emergency, is there some command to just create a new MBR?

There's nothing wrong with your system.

Only thing that happened is by putting in the other disk, the boot sequence changed.

Go in the BIOS, and change the first device to boot to the old drive.

Don't mess around with the W7 install, you might ruin it.

Good luck.

 

[comdude85]

The BIOS boot sequence is correct, double checked that after I first saw the problem. What I don't get is how if bootrec.exe /scanos finds my OS install, how come bootrec.exe /fixmbr won't solve the problem... fixmbr has never let me down with other versions of Windows...

 

[comdude85]

Several times in a row, the Startup Repair function has reported "The partition table does not have a valid System Partition." as the root cause, and claimed to have repaired it. It has not. I can't imagine what partition is missing since, as I said, I can see my data just fine from the command prompt.

 

[SquonkSC]

The BIOS boot sequence is correct, double checked that after I first saw the problem. What I don't get is how if bootrec.exe /scanos finds my OS install, how come bootrec.exe /fixmbr won't solve the problem... fixmbr has never let me down with other versions of Windows...

Just a question.

You said you can go to the prompt, and you see C:\ right?

When you type dir and press enter, do you see the directories, like program files, and windows?

 

[comdude85]

Yes, all of my data is there.

 

[SquonkSC]

Yes, all of my data is there.

Did you install a new second disk or a used one?

 

[comdude85]

Brand new, unformatted.

 

[SquonkSC]

Brand new, unformatted.

Have tried what happenes when you disconnect the new drive?

Does Windows boot then?

 

[comdude85]

Unfortunately it does not

 

[SquonkSC]

Unfortunately it does not

Hmm.

Could you tell me the sequence of events, from where W7 was fine until it wasn't?

When you installed the new drive, was that the end for W7, or did that happen later?

What I suspect is that in first instance, the boot sequence in the BIOS was set to boot the new drive, and maybe you changed it later.

Meanwhile the multitude of repair attempts have ruined your install.

Correct me if this is not the way it went.

 

[SquonkSC]

Meanwhile you can try these commands.

bootrec /fixboot
bootrec /RebuildBcd

 

[comdude85]

bootrec /fixboot returns "Element not found." bootrec /RebuildBcd scans, asks if I want to add C:\Windows to the boot list, and when I type Y it returns "Element not found."

The MBR went away at the same time I installed the second hdd. The BIOS boot sequence never changed. I don't see how my install could be ruined if all of my data is still present, I just can't figure out how to get the MBR set.

 

[SquonkSC]

bootrec /fixboot returns "Element not found." bootrec /RebuildBcd scans, asks if I want to add C:\Windows to the boot list, and when I type Y it returns "Element not found."

The MBR went away at the same time I installed the second hdd. The BIOS boot sequence never changed. I don't see how my install could be ruined if all of my data is still present, I just can't figure out how to get the MBR set.

It sounds very much like a damaged boot sector. (lets hope not.)

The best thing to do is to install w7 on the new disk.
When done, copy the user files from the damaged disk to the new.
(You will have to take ownership of the whole partitions of the old disk,
and also add your username to the security list with full permissions.)

And with a partition program delete all partitions, make a new one, and see if the old drive is usable.

Good luck.

I have to go to bed now.

I'll check in tomorrow.

Greetz

 

[comdude85]

Well, I installed 7 on a spare HDD (didn't want to put any MBR voodoo on the new one, because it's just going to be my data drive... gotta love 2TB on sale!), copied the whole OS drive over to that, unplugged that one, installed 7 on the original OS drive, plugged in the new drive, and it boots! I do appreciate the speed with which 7 installs, considering I went from a perfectly happy 7 install, to nothing, to 2 more installs in separate hdds in less than 5 hours after UPS delivered my new hdd...

 

[SquonkSC]

Well, I installed 7 on a spare HDD (didn't want to put any MBR voodoo on the new one, because it's just going to be my data drive... gotta love 2TB on sale!), copied the whole OS drive over to that, unplugged that one, installed 7 on the original OS drive, plugged in the new drive, and it boots! I do appreciate the speed with which 7 installs, considering I went from a perfectly happy 7 install, to nothing, to 2 more installs in separate hdds in less than 5 hours after UPS delivered my new hdd...

Awake again, short sleep.

Yes, install speed of W7 is phenomenal.

So I understand you are a happy customer again?
Everything up and running?

 

[MaliciousOne]

Bootrec.exe /FixMbr

Bootrec.exe /FixBoot

Bootrec.exe /RebuildBcd

After done reboot.
If that doesnt work repeat the above but before reboot type -

Bootsect.exe /nt60 all /force