Master Boot Record

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

http://www.thewindowsclub.com/repair-master-boot-record-mbr-windows

If this MBR mean, Master Boot Record, it's a DOS-alike thing.
You require a DOS or Windows 95 / 98 bootflop, containing the program FDISK (forgot if it was .com or .exe)

After booting you get the DOS-prompt which is text-based and looks like :

"A:>_" or "C:>_"

Now, in this case you enter the following: "fdisk /mbr"

So the DOS-prompt will look like :
"A:>fdisk /mbr" or "C:>fdisk /mbr"

Then you hit the ENTER-button at your keyboard and if DOS can find this fdisk-program, it will rewrite the master boot record of your harddisk.

You may need to press F12 to select the boot device. Then you want to select the hard drive your operating system is installed on.

Boot Manager

A boot loader, also called a boot manager, is a small program that places the operating system (OS) of a computer into memory. When a computer is powered-up or restarted, the basic input/output system (BIOS) performs some initial tests, and then transfers control to the Master Boot Record (MBR) where the boot loader resides. Most new computers are shipped with boot loaders for some version of Microsoft Windows or the Mac OS. If a computer is to be used with Linux, a special boot loader must be installed.It also allows multiple operating systems to be booted from the same computer.

This file contains the information where the system file is located.

The message you are encountering could be due to corrupt MBR or Corrupt hard drive.

Usually CHKDSK command fix this problem but as you can boot the system you will bot be able to run the command.

Download "Hiren's Boot CD" using the link below

http://hirens.longcomputerservices.com/Hirens.BootCD.10.1.zip

extract the downloaded file with winzip or winrar and burn it in a CD.

now boot the system using that CD (set your BIOS to boot from CD-DVD ROM).

you will have access to repair tools for Hard drive, MBR fix etc etc.i recommend you fgo for CHKDSK command

it will solve your problem.

you can have a look on the internet for a boot cd called hirens boot cd and download burn it and boot it from cd then go into mbr tools and choose a mbr program to repair and it should work after that