after installing 25H2 update my C: drive is encrypted by Bitlocker

It sounds like your laptop entered BitLocker recovery mode after the update to 25H2. This can happen for several reasons, especially if there were changes to the system configuration, such as a motherboard replacement. BitLocker is designed to protect your data by requiring a recovery key if it detects changes that could indicate a potential security risk.

Here are some key points to consider:

1. Motherboard Change: Changing the motherboard can trigger BitLocker recovery because it alters the hardware configuration that BitLocker uses to validate the system. This is likely why you were prompted for the recovery key.
2. System Updates: Major updates, like the 25H2 update, can also affect the system's integrity checks. If BitLocker detects any discrepancies during the boot process, it may enter recovery mode.
3. Recovery Key: Since you found your recovery key and entered it, you should be able to access your system. If you continue to have issues, ensure that you back up your recovery key in a safe place to prevent future access problems.
4. Future Updates: To prevent BitLocker from entering recovery mode during future updates, consider suspending BitLocker before applying significant updates, especially those that involve firmware or hardware changes.

If you're still having trouble accessing your C: drive after entering the recovery key, you may need to explore additional recovery options or consult with IT support for further assistance.

When I fill in the key I was expecting it to unlock itself (like on movie) but I only get biu screen alternativs. Is that was is to be expected? What do I do next after the blue screen cubes show up?

Best regards

[Moderator note: personal info removed]

Hi @Kenth Andersson, 

Welcome to Microsoft Q&A forum. 

I understand your laptop is returning to the recovery screen even after accepting the correct BitLocker key following the 25H2 update. 

This behavior typically occurs when the security chip (TPM) requires manual verification of the new system files. To help resolve this, we need to temporarily suspend BitLocker protection via the Command Prompt, which will allow the system to reconfigure its security trust and boot normally.

Please follow the instructions below from the "blue screen" menu you are currently seeing: 

1. Access command prompt: 
   • Firstly, select Troubleshoot > Advanced options > Command Prompt. 
   • If prompted, select your user account and enter your Windows login password (not the BitLocker key). 
2. Unlock and suspend BitLocker: 
   • When the black Command Prompt window is open, type the following command to check your drive letter (usually C:) and press Enter: manage-bde -status 
   • Then verify which drive is the "OS Volume" and locked. If it is C:, type the command below to unlock it (replace the X's with your 48-digit recovery key) and press Enter: manage-bde -unlock C: -rp XXXXXX-XXXXXX-XXXXXX-XXXXXX-XXXXXX-XXXXXX-XXXXXX-XXXXXX  Note: If the command works, it will say "The password successfully unlocked the volume." 
   • Type the following command to suspend the security check for the next reboot and press Enter: manage-bde -protectors -disable C: 
3. Restart: 
   • Type exit and press Enter to close the window. 
   • Select Continue (Exit and continue to Windows 11). 

For your reference, you can find more technical details regarding the manage-bde tool and recovery scenarios in the official Microsoft documentation here: BitLocker recovery guide - Microsoft Learn 

Please attempt these steps and let me know the outcome. If the system successfully boots to your desktop, please remember to search for "Manage BitLocker" in the Start menu and select Resume Protection to ensure your drive is encrypted again. 

If the issue persists or if you encounter any specific messages in the Command Prompt, please reply with those details so I can investigate further.

I'm looking forward to your reply.

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