windows - Recover MBR after overwriting it with an empty one

I've accidentally messed up my Windows XP hard drive.

I wanted to copy the MBR from this disk to a new SSD, but I've done the opposite. I do not have a shadow copy of that volume and thought that just messing with the MBR can be recovered. Unfortunately, I'm not able to bring my Windows XP HDD back to life.

I used this command dd if=/dev/sda of=/dev/sdb bs=512 count=1 and I know that I've overwritten just the first 512 clusters. The problem is I can't revert it.

Recovery steps attempted:

• I've tried FIXMBR and FIXBOOT using the Windows XP installation disk.


• I've also tried also using TestDisk from a GParted Live CD - it successfully found my partition table, wrote it, but still no success.


• I tried rebuilding bootcfg and MFT - the operation succeeded, but still no luck.


• Under the Windows XP recovery console, I tried both CHKDSK /P /R and even repairing the whole installation - but I still can't boot into my Windows. It just throws up Read Error Occured, Press Ctrl+Alt+Del.

If I hook up this drive up via a USB case for SATA drives, it throws up a Windows error 0x000007b while booting (I can see the Windows XP boot screen for a few seconds).

Can you please advise me what else I can do? (Or what I've done wrong in any of my attempts?)

TestDisk can list my files and I'm able to copy them to an external drive, but I want to avoid a clean installation.