When is the MBR created or made? I was wondering say in a situation where somebody had installed GRUB or GRUB-2 to the MBR, what will restore the MBR to its pristine condition? Will doing what the hard disk manufacturer calls a low-level format restore or delete the MBR. Does an OS like Windows XP or Windows 7 completely overwrite the MBR?
Hello NGC 3242, welcome to Seven Forums!
No, no kind of format will remove/over-write Grub, a complete wipe of the HDD must be done, I would suggest, after you have copied out or made back-ups of the data you need to save to external media, use Step One of this tutorial at the link below to do a wipe (secure erase) to the entire Hard Disk Drive, running this then using the outline in Step Two #2 to create/format and mark Active a single 100GB partition using diskpart will get you the best possible space to clean install Windows 7 to.
SSD / HDD : Optimize for Windows Reinstallation
DISKPART : At PC Startup
Be sure to post back with any further questions you may have and to keep us informed.
Note
Contrary to popular belief, doing a format with Windows 7 does not remove any data at all, it just checks for sector errors and marks the space to be over-written as needed, all the data is still there including all the code from previous/failed installation attempts.
Okay you’re saying a wipe of the hard disk will overwrite the MBR. I have a Western Digital data lifeguard utility that can write zeros and ones. For my Samsung hard drive I have their Estool 301 diagnostic utility which has an option for a low-level format. I believe it also just write zeros and ones to the hard disk as well but I don’t want to test it now as I have data on that hard drive. I also have the ultimate boot 5.0.3 desk that has over a half dozen wipe utilities on it.
What about FDISK/MBR. Will that overwrite the entire master boot record or only restore the parts of the master boot record related to DOS?
And if running a wipe of the hard disk by writing zeros and ones to it is the only sure way to delete the MBR, could one run the program for just say two minutes? Which end of the hard disk does the wipe start at?
I’m just trying to figure out what is the easiest and fastest method overwrite the MBR completely.
Apply one set of zeroes using Data Lifeguard CD.
It isn't a fast process, so expect about an hour per 300gb.
To answer your other question: The MBR is created when disk is first initialized and user chooses MBR vs. GPT formatting. It can be changed in Disk Management. http://en.wikipedia.org/wiki/Master_boot_record
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