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I have a corrupt mbr and need to know if the following commands will delete my data or just create a new bcd area for bootstrapping?


bcdedit /export C:\BCD_Backup
cd boot
attrib bcd -s -h -r
ren c:\boot\bcd bcd.old
bootrec /RebuildBcd
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My friend had a MBR virus thing, the usual MBR fixing did not function normally. At any rate i was not going to risk any data. Fixing the MBR is not supposed to cut into any data, or damage the parttition tables (etc) . But stuff doesnt always go as planned, or work as designed. We HAD TO secure the data first. and we had to do so without exposing another drive , in "boot". So we transferred the data with net or links. in the end we decided to wipe everything, and start over. I dont understand it completly, but even if i did i would have to secure the data first. – Psycogeek Dec 29 '11 at 7:54
up vote 3 down vote accepted

This will fix the BCD store.

To fix the MBR, you need to use bootrec /fixmbr

To fix the Boot Sector, use bootrec /fixboot

I can be difficult to tell exactly where the boot process is breaking. But in general it goes, MBR to Boot Sector to BCD store IIRC.

I usually just go in order to fix something. FixMBR, then FixBoot, then BCD. Or just let Windows repair, which is faster.

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Thanks for the reply. Ok, thanks for being clear. However, I just want to make sure that either command whether it be BCD commands or the /fixmbr or /fixboot will NOT delete any of my data? Can you confirm? – JaJ Dec 29 '11 at 7:35
Also, here is the last thread that I posted and I have yet to get my back into my data because of bit locker issues,…. – JaJ Dec 29 '11 at 7:35
Ya, it won't touch your data or partition tables. – surfasb Dec 29 '11 at 8:46

Had the bootmgr missing....

I booted from USB which has RepairDiscWindows7-64-bit.iso on it. Did the:

bootrec /fixmbr
bootrec /fixboot
bootrec /rebuildbcd

one after the other, but no joy. I got "0 windows install".

Then I exited out of the command prompt, went to the startup repair from the system repair options. It went through the repair thing, and then booted to the sign in screen.

You may have to do the repair more than once.

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