Bitlocker can be used to encrypt your drives from PowerShell, leaving you unable to access them after a reboot.
Stop PowerShell from interating with the Bitlocker Application
Through our Suggested Policies, you can prevent PowerShell from calling the Bitlocker Application.
Navigate to Application Control > Policies
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Select the desired level from the Applies To dropdown menu on the top right.
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Select the 'Add Suggested Policies' button.
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Click to Deploy Policies.
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This will prevent PowerShell from calling the Application and running the manage-bde.exe commands.
Removing PowerShell's access to the Bitlocker Module
In addition to the above Ringfencing policy, you need to create a Storage Policy to remove access to the Bitlocker PowerShell module and the Enable-Bitlocker commands.
Navigate to Storage Control > Policies
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Select the desired group from the Applies To dropdown menu on the top right.
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Select 'New Storage Policy'.
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Enter a name for the Policy and change 'Permit' to 'Deny Read & Write'.
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Under the 'What paths should this apply to (e.g. '\\server1\share\*", "*.jpg" or "regex:[0-9]abc")? ' section, check 'Let me select file paths', then input the following into the text box and select 'Add':
c:\windows\system32\windowspowershell\v1.0\modules\bitlocker\*
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Select 'Save'.
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Then Click to Deploy Policies.
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