Hi. Thank you for your question and reaching out. I’d be more than happy to help you with your query
The error message you are encountering is indicating that the TPM (Trusted Platform Module) is not available or not compatible with BitLocker, and the policy to allow BitLocker without a compatible TPM is not enabled.
To resolve this issue, follow these steps:
Open the Local Group Policy Editor: Press the Windows key + R, type "gpedit.msc" and press Enter.
Navigate to Computer Configuration > Administrative Templates > Windows Components > BitLocker Drive Encryption > Operating System Drives.
Locate the "Require additional authentication at startup" policy and double-click it.
Change the policy setting to "Enabled" and select "Allow BitLocker without a compatible TPM".
Click OK and close the Group Policy Editor.
Restart the computer and try to encrypt the OS drive again using BitLocker.
Note: If you don't have access to the Local Group Policy Editor, you can use the Registry Editor instead. To do this, press the Windows key + R, type "regedit" and press Enter. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\FVE and create a new DWORD value with the name "RequireTPM" and set its value to "0".
This should resolve the error and allow you to encrypt your OS drive with BitLocker.
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