What gets fixed with the FIX/MBR Utility

[Guest]

I have a system that is booting just fine into Windows Xp sp2+. However, I
have been using the "TrueImage" backup software for 2 years to make Images of
each of my Partitions, ie. Drive C , D, etc. There are 4 partitions of 20 GB
each on an 80 GB drive. The problem is that I made a small change to my
system and now the TrueImage "boot" cd will not boot. Neither will their
Floppy boot program. They say the problem "could be" my master boot record
and want me to download a disk to fix this. I don't get it, they must
boot first to their own CD, then attempt to access the MBR on each hard drive
to find out what the drives are, what the partitions are, etc, so they can
then proceed with a backup of the image.

What could be wrong with the MBR that they can't use when it will boot just
fine in Windows.

 

[Lenard Lund]

The Master Boot Record of your hard drive

 

[Guest]

Lenard,... I meant more specifically, what does it do. Of course if fixes
the MBR, but how. Does it first check to see what is wrong. How does it
"FIX" it. Does it look at all the partitions on that drive and recreate the
MBR. Does it search for the backup MBR and copy that over. I have seen
other posts that say "If there is nothing wrong with the boot record, what is
there to fix. Some say "if it is corrupt, it will be fixed,...I ask "how
will it be fixed" where did it get the info to fix,.. or is it just going to
create a new "Default MBR" that will really erase all the partition
information that is there now. I'm not having a problem that I know of but
TrueImage software seems to think three is a problem with my MBR.

 

[Steve N.]

Lenard,... I meant more specifically, what does it do. Of course if fixes
the MBR, but how. Does it first check to see what is wrong. How does it
"FIX" it. Does it look at all the partitions on that drive and recreate the
MBR. Does it search for the backup MBR and copy that over. I have seen
other posts that say "If there is nothing wrong with the boot record, what is
there to fix. Some say "if it is corrupt, it will be fixed,...I ask "how
will it be fixed" where did it get the info to fix,.. or is it just going to
create a new "Default MBR" that will really erase all the partition
information that is there now. I'm not having a problem that I know of but
TrueImage software seems to think three is a problem with my MBR.

It re-wrties just the boot code, not the partition tables in the MBR.

Second hit on a Google search...

http://www.microsoft.com/resources/documentation/Windows/XP/all/reskit/en-us/prkd_tro_ldau.asp

"You can use the fixmbr command in Recovery Console to rewrite the MBR
to resolve a corrupted MBR on a startup disk. However, running fixmbr
overwrites only the master boot code, leaving the existing partition
table intact. If the corruption in the MBR affects the partition table,
running fixmbr might not resolve the problem."

Steve N.

 

[Robert Roland]

or is it just going to
create a new "Default MBR" that will really erase all the partition
information that is there now.

The term "MBR" is used differently by different people. Sometimes,
"MBR" refers to the entire first sector of the disk. This sector
contains two main parts: the partition table and a chunk of executable
code. Sometimes this chunk of executable code is referred to as the
"MBR".

FIXMBR does not touch the partition table, but overwrites the chunk of
executable code with a standard Windows code. This means that, if you
have a custom MBR, such as a Linux boot loader, Partition Magic etc.,
it will be overwritten and your custom functionality will be lost.

The Windows MBR code does essentially three things:

1. Find where the first sector of the active partition is.
2. Load that sector into memory.
3. Execute the loaded sector.

 

[Guest]

Robert Roland. Thnaks very much for your answer to this question and the
"Detail" that you provided. I had talked to the "Floor Manager" at the
Microsoft Help Support area and he assured me that ""If your system boot and
runs programs within Windows Xp, there is nothing wrong with your MBR". Also
he said for sure, if you run FixMbr it will destroy all the partitions on
that drive.

It seems you can't trust anyone in the computer Technology and it is best to
get 2-3 answers. Your answer seem much more logical.

When I run the run the TRUEImage boot disk I get the following error; "
Acronis loader fatal error: Logical Disk for boot Drive not found."

I am going to make new backups of all partitions on that drive before I do
anything. Then if I try to FixMBR and it fails I feel I can always wipe the
disk clean and re-create all partitions and reload them.

Thanks for you help.