Restore boot manager when it is missing or compressed

Windows Vista includes a new Boot Manager (BootMgr) that replaces the old NT Loader (Ntldr).

If you don’t have the install DVD, then go ask friends/family/work whether they have a disc you can borrow. If your computer cannot boot from a DVD, then you can use another computer to Create a Windows Vista/7 Recovery disk on an USB stick.

Boot Manager is missing

If the boot partition no longer can be found, then Vista will display the following error:

BOOTMGR is missing. Press Ctrl+Alt+Del to restart

The Windows Boot Configuration Data file is missing required information

More Info MS KB919529
More Info MS KB927391
More Info MS KB2622803

Check points for fixing missing boot-manager:

Boot Manager is compressed

If by accident having compressed the entire boot partition, then Vista will display the following error:

BOOTMGR is compressed. Press Ctrl+Alt+Del to restart

Check points for fixing compressed boot-manager:

  • Boot into Windows Recovery Environment (WinRE) and perform a “Startup Repair”.
  • If the above doesn’t solve the problem then boot into WinRE again, but when selecting the Vista-installation, then press “Load Drivers” (Instead of “Next”) and use the mini Windows Explorer to right-click the boot-drive and deselect “Compress this Drive” and choose Apply to sub-folders and files.
  • If that also fails then boot into WinRE again, and go to the “Command Prompt” and execute these commands:

    compact /U C:\bootmgr compact /U C:\ntldr

  • If you for some strange reason have lost your Vista DVD, then you can also use a Windows 2000 / XP install CD and enter the recovery console instead and execute the following commands:

    attrib -c c:\bootmgr attrib -c c:\ntldr