Which MBR fix is correct?

[markg2]

My wife's computer periodically issues 'bootmgr is missing' on boot. I use an Acronis boot disk in those instances to successfully load Windows. Norton comes up clean and so does Malwarbytes. I ran the Norton Eraser in the event there was a rootkit problem and it too came up clean.

Therefore I'm assuming there's something messed up with the MBR.

I've researched repairing the boot loader and found 2 similar but different command prompt commands and wish to get a clarification here before I proceed.

Method 1: Select command prompt from the system recovery options on the OS disk. Type 'bootrec /fixmbr' to restore the master boot record.

Method 2: At the command prompt, successively type each of the following commands followed by a CR:
bootrec /FixMbr
bootrec /FixBoot
bootrec /RebuildBcd

?

Mark

 

[andrew129260]

See this walk through tutorial:

http://www.sevenforums.com/tutorials/20864-mbr-restore-windows-7-master-boot-record.html

 

[mjf]

For Windows 7 I would opt for the method 2 / bootrec approach.
My understanding is that Bootsect is still supported more for backward compatibility (eg. to include NTLDR boot loaders in dual boot W7 / XP) and doesn't do everything bootrec does.

http://technet.microsoft.com/en-us/library/cc749177%28v=ws.10%29.aspx
http://support.microsoft.com/kb/927392

 

[smarteyeball]

+ another for Option 2

 

[markg2]

I followed through Andrew's link and sort of come back to a tangent of my initial question.

Although, practically it may not be, browsing through the screens step by step the procedure conveys a sense of having a ton of steps and a procedure that could (when doing for the first time) could lead to failure by way of user input error.

At the very end of Andrew's link, a screenshot says: "NOTE: If this method fails to restore the MBR, you can try the bootrec command as it is also a tool for repairing the MBR.", which to me, begs a variant of my initial question: WHY go through all of Andrew's steps if all I have to do is simply type:

Method 1: Select command prompt from the system recovery options on the OS disk. Type 'bootrec /fixmbr' to restore the master boot record.

and if that doesn't do the trick... reboot off the DVD and execute ALL 3 of the steps listed below?

Method 2: At the command prompt, successively type each of the following commands followed by a CR:
bootrec /FixMbr
bootrec /FixBoot
bootrec /RebuildBcd

Makes any sense?

Mark

 

[mjf]

WHY go through all of Andrew's steps if all I have to do is simply type:......

You were given alternate opinions (and links) which you chose to ignore.

 

[whs]

The command promt fixes never worked for me. Best is to do a startup repair 3 times.

http://www.sevenforums.com/tutorials/681-startup-repair.html

Make sure you reboot after each time.

 

[mjf]

Startup repair is another option but takes longer and isn't solely focused on fixing the boot chain - Bootrec is. I haven't had a problem with Bootrec but wouldn't reject startup repair. I have had startup repair hang on me.
Now you have another option.

 

[markg2]

Results:

bootrec /FixMbr-->Operation completed successfully
bootrec /FixBoot-->Operation completed successfully

bootrec /RebuildBcd-->Total identified Windows installation=0, Operation completed successfully

How can the operation be successful if there was no Windows installation found????

 

[mjf]

Post a disk management screenshot.
(You need an active partition)

I also refer you to
http://support.microsoft.com/kb/927392
in particular

"If rebuilding the BCD store doesn't resolve the startup issue, you can export and delete the BCD store and then run this option again. By doing this, you make sure that the BCD store is completely rebuilt.

To do this, type the following commands at the Windows RE command prompt:

• bcdedit /export C:\BCD_Backup
• c:
• cd boot
• attrib bcd -s -h -r
• ren c:\boot\bcd bcd.old
• bootrec /RebuildBcd

"

 

[markg2]

To clarify--

I'm inclined to believe that I fixed whatever problem lurked within the MBR. The problem that she was experiencing was a 'random' boot load failure. The boot stop seemed to be associated with a more 'energetic' boot typically after a raft of updates. I've now updated her machine 3 times post my MBR attempted fix and all with required boots and all attempts have booted just fine to this point. That is not to infer the problem is no more. The only sure fire way of confirming that is more time and more boots.

Yesterday, at the time of repairing her MBR, since I did not run the switch /scanos and she clearly has an active (C) partition (attachment), I remained confused why the switch /RebuildBcd unsolicitously returned (in addition to a successful result) "Total identified Windows installation=0"

 

[mjf]

T I remained confused why the switch /RebuildBcd unsolicitously returned (in addition to a successful result) "Total identified Windows installation=0"

This is reported by others and I admit it is a confusing message. My guess was that the BCD had an entry for a Windows "Winload.exe" but that this was wrong and you had to delete the BCD before rebuilding. This is described at the end of the MS guidance I referred you to. However, the PC is booting so I am also a little confused would hope
bootrec /scanos
would identify an OS.

Aside:
I don't know specifically about Lenova but the SYSTEM_DRV looks a little odd to me in that it has a lot of free space.

 

[markg2]

The Bootrec /scanos reports essentially the same information as did bootrec /RebuildBcd: Total identified Windows installation=0, Operation completed successfully.

It's possible that the clue to this mess is the automatic scan screen that occurs just before the repair screen listing one's action options.

The result was of that automatic scan:

Operating system Partition size Location
Windows 106603 E<----patently wrong

Somehow the diagnostic is seeing the active partition as E whereas it's clearly C (re: my disk management post earlier in the thread).

The E drive is my wife's 2 of 2 physical data only drive (a third data only, D, is attached externally using USB)

I have no clue as to how the repair disk finds the active disk to be on one drive and the loaded OS vis a vie disk management finds the active disk to be totally different.

FWIW, the active drive C is an SSD.

Mark