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 c: cd boot attrib bcd -s -h -r ren c:\boot\bcd bcd.old bootrec /RebuildBcd
This will fix the BCD store.
To fix the MBR, you need to use
To fix the Boot Sector, use
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.
In case you need a visual guide to help you fix the MBR, check this step by step tutorial: Command Prompt - Fix Issues with your Boot Records. I hope you will find it useful.