Decrypt all of the BitLocker encrypted drives

I needed Bitlocker actually OFF, not just suspended, so here's the script that I used to ensure that it got there:


For Win10:
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#Decrypt-BitlockerDrives.PS1
#Script by Mark Randol
#randoltech.blogspot.com
#This script finds all local encrypted volumes and decrypt them.
#Does not exit until decryption is completed.

CLS
Clear-BitLockerAutoUnlock #Since we're decrypting all of the drives, and any Auto-Unlock protectors are tied to the encryption on the system drive, these need to go away.

$PossibleDrives = (Get-BitLockerVolume).MountPoint  #get all of the drives that could possibly be encrypted

#Disable-BitLocker -MountPoint $PossibleDrives #start all of the discovered drives decrypting in parallel

foreach ($DriveLetter in $PossibleDrives) {  #step through the drives in series to ensure they get decrypted
    [int]$LastEncryptPercent = 100  #This variable stores the most recent change to the encryption percentage 
    [int]$CurrentEncryptPercent = 2  #This variable stores the current check that we are making on the encryption level
    #If these two variables are equal we know that no progress has been made in decryption since the last check
    do { #check the encryption level of the drive every five minutes until it is fully decrypted
        $CurrentEncryptPercent = (Get-BitLockerVolume -MountPoint $DriveLetter).EncryptionPercentage
        if ($CurrentEncryptPercent -ne $LastEncryptPercent) { #if the percentage of encryption has changed since the last check then write that to the output
            $OutputString = "Drive " + $DriveLetter + $CurrentEncryptPercent.ToString() + "% encrypted"
            Write-Output $OutputString
            $LastEncryptPercent = (Get-BitLockerVolume -MountPoint $DriveLetter).EncryptionPercentage #Since the encryption percentage has changed, lets store the this percentage as our "last" (most recent)
        }
        Start-Sleep -Seconds 300  #wait five minutes before checking again
    }
    while ($CurrentEncryptPercent -ne 0)
}
Write-Output (Get-BitLockerVolume)

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For Win7

#Decrypt-BitlockerDrives.PS1
#Script by Mark Randol
#randoltech.blogspot.com
#
#This script will list out all of the encryptable volumes on the local machine and decrypt them
#Do not exit until decryption is completed.
#there are simpler ways to do this with modern Powershell commands (Get-BitLockerVolume for example)
#but those methods do not work with a native Windows 7 PowerShell environment so this was
#developed to help facilitate Windows 7 to Windows 10 migration.
$WMINameSpace = "root\CIMv2\Security\MicrosoftVolumeEncryption"
$WMIClass = "Win32_EncryptableVolume"
$BitLockerDrives = (Get-Wmiobject -Namespace $WMINameSpace -Class $WMIClass -ComputerName $env:COMPUTERNAME).DriveLetter
foreach ($LockedDrive in $BitLockerDrives) {
    $Status = (Get-Wmiobject -Namespace $WMINameSpace -Class $WMIClass -ComputerName $env:COMPUTERNAME -Filter “DriveLetter=""$LockedDrive""”).ConversionStatus
    if ($Status -ne 0) {
        if ($Status -eq 1) {
            Invoke-Command {manage-bde.exe -off C:}
        }
}
foreach ($LockedDrive in $BitLockerDrives) {
    $Status = (Get-Wmiobject -Namespace $WMINameSpace -Class $WMIClass -ComputerName $env:COMPUTERNAME -Filter “DriveLetter=""$LockedDrive""”).ConversionStatus
    if ($Status -ne 0) {
        do {
            Start-Sleep 15
            $Status = (Get-Wmiobject -Namespace $WMINameSpace -Class $WMIClass -ComputerName $env:COMPUTERNAME -Filter “DriveLetter=""$LockedDrive""”).ConversionStatus
        }
        until ($Status -eq 0)
    }
}
{Exit $LASTEXITCODE}