Note: Some business-line PCs may come with pre-installed non Windows OS like FreeDOS. These systems most probably use Linux as there main boot system and this is why a typical Windows installation may not boot properly in some cases.

Case: Install Windows 7 (64bit)

  1. Boot with a Windows 7 (64bit) setup DVD and install windows
  2. If your system loops on restart then you may need to do as follows:

[bash]#Type the following to take you to MS DiskPart prompt
diskpart
#The next command will select a disk to proceed
select disk 0
#Type the next command to see a list with system volumes.
#Note down the CD/DVD drive letter i.e. “E”
list volume
#The next command will take you back to command prompt
exit
#Type the following to take you to drive E
e:
#cd into the boot dir
cd /boot
#Type next command to reset the MBR
bootsect /nt60 SYS /mbr[/bash]

Credits: SevenForums