Windows 10: [HELP] Bitlocker decryption stuck at 82.1% No disk activity

I have been decrypting bitlocker on my USB disc drive for the past two days, and I recently noticed that it had been at "82.1% Completed" for hours. Task manager now shows 0% disc activity for the drive, whereas before it was 100% for the past two days.


Drive: 4TB USB HDD drive Bitlocker full encrypted, auto-unlock enabled. Recovery key working.

Main usage: Backups

Unique information on the drive: 1TB of data not backed up anywhere else

Windows version: 10 Pro 64-bit 1909

Bitlocker version: 2.0

USB port: 3.0


What I have tried:

1a. Pausing and resuming BitLocker

1b. Rebooting the machine and trying again

1c. Booting into safe mode and trying again

1d. Booting into recovery mode X:\ administrator command prompt and using "manage-bde"

1e. Disabling Secure Boot in the BIOS and trying again

1f. Enabling CSM in the BIOS and trying again

1e. Using "manage-bde" to pause, resume, start encrypting and then start decrypting again on steps 1b, 1c, and 1d.

1f. Connecting the drive to another Windows 10 Pro 64-bit computer and trying steps 1a and 1e.

1g. Running "chkdsk" in an administrator command prompt, and via the GUI version in drive properties, both said no errors were found.

1h. Attempting to use "repair-bde F: G: -rp [Full recovery password, that has been tested and is working] -Force", however I don't have another drive that is 4TB capacity the "G" drive is a 32GB USB stick. Output:

Bitlocker Drive Encryption: Repair Tool version 10.0.18362

Copyright C 2013 Microsoft Corporation. All rights reserved.


LOG ERROR: 0xc000003d

Needs at least 3815318 MB of free space for repair.


ERROR: Not enough free space on output volume to perform repair.



What I have observed:

1. 30-60% disc activity on the drive for about a second on steps 1a, 1b, 1c,

2. 100% disc activity on the drive when using "manage-bde -on F:" re-encrypting the drive

3. 100% disc activity on the drive when using "manage-bde -off F:" decrypting the drive again AFTER step 2, but only until I assume BitLocker gets to the same place where it was stuck before, as disc activity drops to 0%. This leads me to believe that BitLocker may be getting stuck in a particular place or on a particular file.

4.


I still have full access to the drive and can read/write perfectly fine. Have successfully viewed files, added files and removed files for testing. I can read/write perfectly fine on both Windows machines I tested on.



TLDR: Bitlocker decryption of a 4TB USB HDD stuck at 82.1% with 0% disc activity for hours. No errors found on the drive, files still fully accessible.



I have already contacted an "IT Pro/Admin" from Microsoft Support who guided me with steps 1e and 1f, but BitLocker still appears to not be doing a lot.

I have also looked at the BitLocker event logs, but nothing about errors is displayed, simply status messages such as "BitLocker decryption was started for volume F:." and "The BitLocker protected volume F: was unlocked. Protector GUID: {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} Identification GUID: {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}"


If you have any ideas or suggestions for fully decrypting the drive, please let me know.

:)

 

BitLocker stuck

Hi Tamnu,

Your concern is more complex than what is typically answered here in Microsoft Answers forums. We suggest to post this query in our
TechNet Forums, where the audience are more inclined when it comes to this type of topic.

You may also check out this thread from the TechNet Forums, as it has an answer to a similar concern like yours:

• Bitlocker Decryption Stuck

If you have further queries, don't hesitate to contact us.

 

Cannot decrypt the disk encrypted by BitLocker

Hi Tom,

Please follow this guideline:

Method 1: Plug in the drive to your laptop and check if you can decrypt it. This shutdown might have been caused by the battery.

Method 2: Following the steps to decrypt the drive:

1. Login, then connect the disk to the computer.

2. Right-click cmd.exe, then select "run as administrator" to launch the command.

3. Type in the following command and press Enter:

manage-bde -off d: (Note you should substitute ‘d’ for the correct drive letter.

You can also get in touch with Microsoft support here: ‘Microsoft Commercial Support’

https://support.microsoft.com/en-us/gp/commerci...

If the methods don’t help, post your query in the TechNet Forum to get further assistance

https://social.technet.microsoft.com/Forums/win...

You might also refer to the following articles:

‘BitLocker’
https://docs.microsoft.com/en-us/windows/securi...

‘Overview of BitLocker Device Encryption in Windows 10’
https://docs.microsoft.com/en-us/windows/securi...

Write me back if it works or not.

Thanks,

Andrew N.

 

Bitlocker Decryption paused and does not resume.

Hi Hamza,



Thank you for writing to Microsoft Community Forums.



I can imagine the inconvenience you are experiencing and will certainly help you in the right direction in fixing the issue.



I suggest you to follow the steps mentioned below to fix the issue.

1. Open the command prompt as admin.
   
2. Type in manage-bde –off <drive> and hit
   Enter.
   
   manage-bde –resume <drive>
   

manage-bde –on <drive>

Replace Drive by drive letter

1. Restart the computer and check the status of the issue
   

You may also refer the article Computer
Crash: How To Use manage-bde To Recover A Partially Decrypted Hard Drive
for the detailed information.



If the issue still persists, I suggest you to post your query in
IT TechNet
forums, where we have a dedicated team of experts who are equipped with the resources to guide you with the further steps to fix the issue.



Regards,

Muralidhar

Microsoft Community Moderator