The Windows Recovery Console, later called the Windows
Command Prompt in Windows Vista and Windows 7, is a
very, very powerful troubleshooting tool.
It allows you to go right on to the operating system and
change things in the file system without actually
starting Windows.
Also keep in mind that this means it is incredibly
dangerous to go into that command line and start making
changes to the operating system down at the OS level.
You should only be using the recovery console or the
command prompt if this is a last-ditch effort to solve
some type of problem on your system.
One advantage this gives you, of course, is that you have
complete control.
You can now get into the operating system before it
starts and make any changes you'd like.
If you're having problems booting your system or you'd
like to make it change to the operating system before it
starts up, this is exactly the place you should go.
You can think about the command prompt or the Windows
recovery console as being able to do things like copying or
changing files that are part of system files and folders.
You can enable or disable services.
You can fix boot sectors and change the Master Boot Record
before your system really gets started.
And you can even change the partitioning, the formatting,
and modify things right at the drive level.
If you didn't want to have to use your Windows XP
installation media every time you wanted to run the recovery
console, you could install it permanently on your system by
grabbing the installation media and
running this program.
You would reference your CD-ROM drive
that had Windows XP.
In the i386 directory you would run winnt32.exe and use
/cmdcons to install the recovery console onto your
Windows XP system.
In Windows Vista you would use the repair utilities under the
system recovery options to go to the command prompt.
And you need your Windows Vista installation media to be
able to do that.
In Windows 7 it's a similar process.
It's almost exactly in the same place if you're using
your Windows installation media.
You can also choose from the Advanced Boot Menu when you
press F8 to start your system to run your repair utilities
from there.
That will only work if you have that 100 megabyte
recovery partition that's built into Windows 7.
And if you're installing Windows 7 from scratch you'll
notice it adds that 100 megabyte partition
automatically.
If you don't have that partition then you will need
to boot from your Windows 7 installation media.
You often need to use these recovery options when you're
not able to boot your system.
And one of the problems you can have when you're booting
your system is a problem with the Master Boot Record.
The Master Boot Record is the very first sector on a
physical disk.
This is exactly where your computer goes before it starts
loading anything from your storage media.
So this isn't in one of your partitions.
This is outside all of the partitions on your system.
But the Master Boot Record knows about all of those
partitions that you've configured on
that particular drive.
It is the master list.
It is your Master Boot Record.
It knows also where the active bootable
partition happens to be.
That is also called the volume boot record.
We'll talk about that in a moment.
So that when the Master Boot Record looks at everything on
your disk it knows exactly where to go to hit the boot
sector for your operating system so that things can
start up normally.
If you run into problems with the Master Boot Record you'll
see messages on the screen like, there's an error loading
the operating system.
Or, missing operating system.
Or, invalid partition table.
All of these problems could point to a problem with your
Master Boot Record.
So how would you fix the MBR?
Well in Windows XP you need to start the
Windows Recovery Console.
Once you're inside of the console you may want to run
something like the MAP command and that would list out all of
the physical drives that are on your computer.
From there, you can use the command FIXMBR and then if you
wanted to, you could even specify a particular device
name that was listed in that MAP command.
If you just simply use FIXMBR by itself, it will use
whatever device is set as the boot device.
With Windows XP we would boot from the boot CD, the
installation CD, for our Windows XP system.
It's going to run through it's normal
process of loading drivers.
And we've seen this before when we went through the
installation process for Windows XP.
It's exactly the same process all the way up until we get to
the very first prompt that deals with
installing Windows XP.
And at that point in our installation program to set up
Windows XP we would have pressed enter.
But in this case we're going to repair a Windows XP
installation by using the recovery console.
So instead we would press R.
When we press R it goes through a process of checking
our keyboard.
And then tells us about all of the Windows installations on
the computer.
It says there is one called C colon backslash WINDOWS.
If there were other Windows installations it would show us
those as well.
And then it gives us a prompt that says which Windows
installation would you like to log into?
And I would like to log in to, number one, the C colon
backslash WINDOWS which is my only prompt in this case.
It wants the administrator password.
And this is an important consideration.
We need to make sure we have the password for our system.
So we need to put in that administrator password.
And if you've got it right you get a C colon backslash
WINDOWS prompt.
You're now at the Windows directory of this computer.
If I type dir here are the files
that are on this computer.
And now I'm able to modify those and make changes before
I even start the operating system.
In this case, let's say we wanted to fix
the Master Boot Record.
Before I do that I want to look at all of the physical
drives on this computer.
I use the map command.
And it tells us there are two.
There's an NTFS drive.
And you can see it's called backslash Device backslash
Harddisk0 backslash Partition1.
There's also a D drive that's my CD-ROM.
And its device name is backslash
Device backslash CdRom0.
What we're going to do is a FIXMBR.
And before I do this I'm going to do a question mark, a slash
question mark so you can see more about
this particular command.
An important consideration is that we're now going to make
changes to the Master Boot Record and that will affect
everything on that physical drive potentially.
We want to be sure, if we have a way to back this system up,
that we do it right now.
If we make a change it is entirely possible that
whatever change we make may render any operating systems
on this computer inaccessible.
And we don't want to have a problem where we're losing
user's data.
What we're going to now run is FIXMBR by itself.
I could also, of course, choose those device names by
specifying device.
I could specify hard disk zero.
And then partition one.
If there were different drives that I wanted to perform that
fix on for the Master Boot Record.
If I hit Enter it says, this computer appears to be
non-standard or invalid Master Boot Record.
And then my particular configuration, my MBR is a
little bit different because of the virtual box system that
are running in this virtualization environment.
And it says, are you sure you want to write a new MBR.
I'm going to Y to say yes.
And a new Master Boot Record has been successfully written.
Now when we restart your system it's going to use this
brand new MBR to get everything else running on
your computer.
If you're running Windows Vista or Windows 7, the
process for recovering the Master Boot Record is a little
bit different, although the concept is exactly the same.
The command is different, however.
It's called BOOTREC for boot recover slash FIXMBR.
So there's a little bit of difference there in what you
use it the command line, but what you're doing to the
Master Boot Record is exactly the same.
Let's run through this recovery process in Windows 7.
Before the operating system had a chance to load I pressed
F8 and that brought me to the advanced Boot Options menu.
You can see at the very top I have an option
to repair my computer.
And the reason that's there is that I have that 100 megabyte
system partition that was created during the Windows 7
start up and so all of the repair functions are on that
100 megabyte partition.
If I didn't have that partition again I would need
my Windows 7 installation DVD and I would boot from that to
get to this repair option.
In this case, I'm going to choose repair my computer.
And we're going to load up all of those repair options that
might be available or need to be used for
this operating system.
The first prompt you get then is for the
system recovery options.
And you can see it asks for a keyboard input method.
The only option that I would like to use in my case is US,
but if you're in another country you would choose the
keyboard that's appropriate for you.
I'll click Next.
And it says you need to log in as a local user.
And I want to get to the command prompt I'm going to
need to log in, not only as a normal user, but the
administrator user as well.
So you'll need to add your password for that
administrator user.
And you get all of these different recovery tools.
You get start up prepare, system restore, system image
recovery, Windows memory diagnostic-- that can be
pretty useful.
And right here is our command prompt.
And if I click that I am now at a
command prompt for Windows.
This looks very similar to any other command prompt in the
Windows operating system, although the number of options
available to me is not quite as many as when I'm running a
full-blown operating system.
This is built just for recovering.
Before I run the BOOTREC command I'm going to use a
command that we used in one of our earlier videos to list out
all of the physical drives that are on this system.
So I'm going to use disk part to go into
the disk part program.
And it tells me what computer I happen to be in and how it's
configured.
And there I am of the disk part prompt.
And I can use a list command.
And if I use a question mark I can list
disk, I can list partition.
I can list a volume or a virtual disk.
In my case, I want to see what disks are available.
There's only one on this particular computer.
I could also a list volume to give you an idea of that since
we're only dealing with the MBR, we're really talking
about what the MBR is for this disk zero.
There's no other disks in my computer so I really can't
mess up this MBR program by specifying the wrong disk.
That's the only one that happens to be there.
So let's exit out of disk part and let's
run our bootrec program.
And I want to fix the MBR.
And what I do that it says the operation is completed
successfully.
That's it.
That's all you have to do.
Now the Master Boot Record has been overridden.
We can reboot our computer and hopefully be passed that
problem we had when we were trying to start it up.
There are other boot records on your computer as well, very
similar to the Master Boot Record but every partition
running an operating system has its own
Boot Record as well.
This is called the volume boot record.
And really it's designed for the individual operating
system that is loaded on that very specific partition.
This starts up the bootloader for that OS.
So if you're running something like Windows XP it's going to
start up the NTLDR application.
If you're running Windows Vista or Windows 7 it runs
something called the Windows Boot Manager.
If you have problems with the volume Boot Record for
operating system you may see errors like this like invalid
partition table.
If you recall, it's very similar to the errors we saw
with the Master Boot Record.
It's very common when somebody's running into these
partition problems and Master Boot Record problems that they
will commonly not only fix the Master Boot Record but they'll
fix the volume boot record at the same time.
To fix the volume boot record in Windows XP we would again
start the Windows Recovery Console.
In this case we would choose the DISKPART command.
This is a little bit different than the DISKPART command
that's in Windows Vista or Windows 7, but it certainly
shows you a listing of the different partitions that are
on your computer.
At that point you can run the FIXBOOT command.
And this will write a new boot sector to the partition that
you specify.
Notice that if you leave it blank whatever you have as the
local device will be the one that gets
the new boot partition.
Here's our recovery console.
If I look at DISKPART it gives me a listing of all of the
different partitions that are on my system.
I really only have one with the drive letter on this
particular computer.
If I had multiple partitions and I could boot into to any
of those I might have a C colon a D colon, an E colon or
other drive letters as well.
This makes it very easy for me to determine which one that
I'm going to fix.
It's only going to have the C colon as an option.
I could even just leave the option off and it will use the
default that I happen to be in because I'm at my
C drive right now.
If I then perform the FIXBOOT and hit Enter it says the
target partition is C colon.
So it does give you an idea of what it will be updating.
Do I want to write a new boot sector to the partition?
Yes I do.
And it says now the file system has been
identified as NTFS.
It's written a new boot sector and it's done.
Just that fast.
And now when I reboot hopefully it will get past all
of those problems that it had either with the MBR or the
individual boot sector for the operating system.
With Windows Vista and Windows 7 we really don't even have to
remember a new command.
With Windows XP we had FIXMBR FIXBOOT.
But with Windows 7 we're still using the BOOTREC command
except we're using a different option after it.
We're using BOOTREC/fixboot to write the new boot sector.
Here's the command prompt in Windows 7.
It's the BOOTREC program again that I'm going to run.
Last time we did a FIXMBR this time we're going
to perform a FIXBOOT.
So it's BOOTREC/fixboot.
And it says the operation completed
successfully just that easy.
Now we can reboot our computer and hopefully we've resolved
that problem with the boot sector.