If your server was booting normally until recently (for example, right before a driver update or application installation), rolling the system state back to a previous point can resolve the issue. Navigate to and select System Restore .
Select the EFI volume (replace X with your volume number) and assign a temporary drive letter (e.g., Z ): select volume X assign letter=Z Use code with caution. Exit Diskpart: exit Use code with caution. Navigate to the boot directory inside the EFI partition: cd /d Z:\EFI\Microsoft\Boot\ Use code with caution. Back up the existing BCD store by renaming it: ren bcd bcd.bak Use code with caution.
The most important takeaway is never to panic and never to format and reinstall as a first response. That last resort wipes configuration, roles, and data. With the commands and techniques outlined in this guide, you can repair the boot process on Windows Server 2012 R2 in 90% of cases without losing your server’s identity and data.
Insert the (ISO, USB, or DVD) into the server. windows server 2012 r2 boot repair
Do begin any repair blindly. Follow these preparation steps first:
UEFI systems do not use traditional boot records; instead, they rely on an containing an .efi bootloader application. The bootrec /fixmbr and /fixboot commands will return errors or fail to work on these configurations. You must manually regenerate the EFI boot files. Re-enter diskpart and list your volumes: diskpart list volume Use code with caution.
: Choose Troubleshoot > Advanced options > Command Prompt to enter the diagnostic shell where all manual repairs occur. II. Automated and Manual Bootloader Repairs If your server was booting normally until recently
Insert your Windows Server 2012 R2 installation media (DVD or bootable USB) into the server and restart it.
If your server is a Domain Controller that enters a boot loop due to Active Directory corruption, restart the server and press F8 (or Fn + F8 ) to access the Advanced Boot Options. Select Directory Services Restore Mode to log in using your local DSRM administrator password. From here, you can troubleshoot services, restore the AD database from a system state backup, or remove problematic updates. Preventative Measures To minimize downtime in the event of future boot failures:
attrib c:\boot\bcd -h -r -s del c:\boot\bcd bootrec /rebuildbcd Use code with caution. Step 5: Verify Integrity and Reboot Exit Diskpart: exit Use code with caution
Nearly all boot repair methods for Windows Server require you to access the . To get there:
If the system cannot find any Windows installations, you may need to export and delete the existing BCD store before rebuilding it: bcdedit /export C:\BCD_Backup . c: (or your system drive). cd boot .
: Your server boots using Legacy/MBR . Proceed to Step 3B .