Windows — Server 2012 R2 Boot Repair

If manual commands are daunting or failing, try the built-in automated repair tool before doing a full manual restore.

If Startup Repair fails, the BCD is likely severely corrupted. Rebuilding it manually using Bootrec.exe is the most powerful fix.

Steps:

bootrec /fixmbr

Writes a new master boot record to the system partition (does not overwrite existing partition table).

bootrec /fixboot

Writes a new boot sector to the system partition.

bootrec /scanos

Scans all disks for Windows installations and displays the results. windows server 2012 r2 boot repair

bootrec /rebuildbcd

Scans for Windows installations and lets you add them to the BCD store.

When you run /rebuildbcd, it will typically find one installation (e.g., "Windows Server 2012 R2"). Type Y (Yes) to add it to the boot list.

Alternative (if /rebuildbcd fails): If the BCD store is beyond repair, you must rename the old BCD and create a new one:

bcdedit /export C:\BCD_Backup
ren c:\boot\bcd bcd.old
bootrec /rebuildbcd

After this, exit the command prompt and restart the server.

In reviewing the typical repair scenarios, three distinct failure patterns emerge: If manual commands are daunting or failing, try

Startup Repair is a built-in automated tool that scans for common boot problems.

How to execute:

What Startup Repair fixes:

Success rate: ~30% for Server 2012 R2. It often reports "Startup Repair couldn't repair your PC." Do not despair—move to Method 2.

To repair 2012 R2, you generally need installation media (ISO mounted or DVD). If Startup Repair fails, the BCD is likely

Windows Server 2012 R2 remains a workhorse in countless enterprise environments, prized for its stability and feature set. However, even the most robust server operating systems are not immune to boot failures. A server that fails to boot can mean downtime, lost revenue, and frantic IT troubleshooting.

Whether you are facing the dreaded "0xc000000f" error, a "Bootmgr is missing" prompt, or an infinite loading loop, this guide will walk you through every possible method to perform a Windows Server 2012 R2 boot repair—from built-in recovery tools to advanced command-line maneuvers.

Sometimes boot failure stems from core OS file corruption, not just bootloader issues. You can run SFC and DISM from the recovery environment.

Steps:

diskpart
list volume
exit

Look for the volume with the label or type "NTFS" and the size of your C drive. Often it’s D: or E: in WinPE. Assume it’s D: in the following commands. 3. Run SFC against that drive:

sfc /scannow /offbootdir=D:\ /offwindir=D:\Windows

dism /image:D:\ /cleanup-image /restorehealth

Note: DISM requires a source. If it fails, you may need to specify a /source pointing to the \sources\install.wim on your installation media.