28 February 2017

Bitlocker Recovery Password Utility

Posted By: Mick Pletcher - 1:20 PM

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Recently, we encountered an issue where we found out a few systems did not have the BitLocker recovery password backed up to active directory. We have the GPO in place that pushes that key to AD, but for some reason, a few systems had gotten by without performing the backup.

I found out that during the build process, a few of those machines had been taken offline before the process had finished, therefore AD wasn't available to receive the encryption password. A couple of others had been accidentally decrypted and re-encrypted therefore the key in AD was no longer valid.

We do have the plan later this year after we deploy Windows 10 to go to MBAM, but before that happens, I wanted to make sure the BitLocker recovery passwords are uploaded to AD.

This script is designed to be run on PCs either one-time or a reoccurring basis. I wrote this script for admins that have SCCM and for those that do not. The script will query the local machine for the BitLocker recovery password. If -ActiveDirectory is selected, it will then query AD for the recovery password(s). If the password matches, nothing occurs. If the password does not match, the script will delete the password in AD and upload the new password. If AD contains the correct password, but there are others also present, the script will delete the other passwords, thereby leaving the correct one in AD.

I have also added a -SCCMReporting parameter if you want to 1) report to SCCM if the recovery password is backed up (boolean value), and 2) if you want the recovery password also reported to SCCM.

For those admins with a simple network setup without SCCM and AD, I have included the -NetworkShare option that will create a file <computername>.txt on the specified network share -NetworkSharePath with the BitLocker password contained within the text file. This method could also be used as a backup to AD if preferred.

NOTE: If you are using this script with active directory, you will need remote server administration toolkit (RSAT) installed on you local machines. The script requires the activedirectory module. One more thing. I cannot stress enough to make absolutely sure this script is functioning correctly on your network. Just because it works on the network this script was written on does not guarantee it will work on another network. You must have PowerShell knowledge to use this script and modify it if needed for your environment. If it does not work correctly on your environment, it could potentially remove good passwords from AD. 

The ideal way to deploy this script is to set it up as a package in SCCM. I have mine configured to run every day at noon time in order to get the maximum number of systems. You could also set this up as a scheduled task.

Here are examples of using the script:
  • Backup recovery password to active directory
    • powershell.exe -file BitlockerRecoveryKey.ps1 -ActiveDirectory
  • Backup recovery password to active directory and SCCM
    • powershell.exe -file BitlockerRecoveryKey.ps1 -ActiveDirectory -SCCMReporting -SCCMBitlockerPassword
  • Backup recovery password to active directory and report AD backup status to SCCM
    • powershell.exe -file BitlockerRecoveryKey.ps1 -ActiveDirectory -SCCMReporting
  • Backup recovery password to network share
    • powershell.exe -file BitlockerRecoveryKey.ps1 -NetworkShare -NetworkSharePath "\\UNC Path\Directory"
This is the best I can do for a screenshot, as a video would expose my BitLocker recovery password. This shows the script being executed and reporting back to SCCM. 


I would like to say thanks to Stephane van Gulick for his Get-BitLockerRecoveryKeyId function that made the rest of this script possible. 

A huge thank you to SAPIEN technologies for PowerShell Studio that made this script a breeze to write. It also helped make this script easy to document for other users to better understand. 



You can download the script from here



 <#  
      .SYNOPSIS  
           Bitlocker Recovery Key  
        
      .DESCRIPTION  
           This script gives the ability to backup the bitlocker recovery key to active directory, SCCM, and/or a network share. If AD is selected, it will query active directory for the latest bitlocker recovery key. Next, it will retrieve the bitlocker recovery key from the local system and then compare the keys to make sure it is backed up to active directory. If SCCM is selected, it will publish the status if the key is backed up to AD and if -SCCMBitlocker Password is selected, it will backup that password to SCCM. It can also backup to a network share if -NetworkShare is selected for admins that do not have SCCM.   
        
      .PARAMETER ActiveDirectory  
           Select this to specify the backing up the recovery password to active directory  
        
      .PARAMETER NetworkShare  
           Specifies to create a text file (<Computer Name>.txt) on the network share specified in parameter -NetworkSharePath. -NetworkShare is intended for admins who do not have SCCM.  
        
      .PARAMETER NetworkSharePath  
           UNC path where to store the text files containing the bitlocker recovery keys.  
        
      .PARAMETER SCCMBitlockerPassword  
           Select this switch if you want the bitlocker password reported to SCCM  
        
      .PARAMETER SCCMReporting  
           Report bitlocker recovery key to SCCM  
        
      .EXAMPLE  
           Backup recovery password to active directory  
                powershell.exe -file BitlockerRecoveryKey.ps1 -ActiveDirectory  
   
           Backup recovery password to active directory and SCCM  
                powershell.exe -file BitlockerRecoveryKey.ps1 -ActiveDirectory -SCCMReporting -SCCMBitlockerPassword  
   
           Backup recovery password to active directory and report AD backup status to SCCM  
                powershell.exe -file BitlockerRecoveryKey.ps1 -ActiveDirectory -SCCMReporting  
   
           Backup recovery password to network share  
                powershell.exe -file BitlockerRecoveryKey.ps1 -NetworkShare -NetworkSharePath "\\UNC Path\Directory"  
   
      .NOTES  
           ===========================================================================  
           Created with:     SAPIEN Technologies, Inc., PowerShell Studio 2016 v5.2.129  
           Created on:       11/14/2016 1:18 PM  
           Created by:       Mick Pletcher  
           Organization:  
           Filename:         BitlockerRecoveryKey.ps1  
           ===========================================================================  
 #>  
 [CmdletBinding()]  
 param  
 (  
      [switch]$ActiveDirectory,  
      [switch]$NetworkShare,  
      [string]$NetworkSharePath,  
      [switch]$SCCMBitlockerPassword,  
      [switch]$SCCMReporting  
 )  
 Import-Module ActiveDirectory  
   
 Function Get-BitLockerRecoveryKeyId {  
        
      <#  
      .SYNOPSIS  
      This returns the Bitlocker key protector id.  
        
      .DESCRIPTION  
      The key protectorID is retrived either according to the protector type, or simply all of them.  
        
      .PARAMETER KeyProtectorType  
        
      The key protector type can have one of the following values :  
      *TPM  
      *ExternalKey  
      *NumericPassword  
      *TPMAndPin  
      *TPMAndStartUpdKey  
      *TPMAndPinAndStartUpKey  
      *PublicKey  
      *PassPhrase  
      *TpmCertificate  
      *SID  
        
        
      .EXAMPLE  
        
      Get-BitLockerRecoveryKeyId  
      Returns all the ID's available from all the different protectors.  
   
   .EXAMPLE  
   
     Get-BitLockerRecoveryKeyId -KeyProtectorType NumericPassword  
     Returns the ID(s) of type NumericPassword  
   
   
      .NOTES  
           Version: 1.0  
     Author: Stephane van Gulick  
     Creation date:12.08.2014  
     Last modification date: 12.08.2014  
   
      .LINK  
           www.powershellDistrict.com  
   
      .LINK  
           http://social.technet.microsoft.com/profile/st%C3%A9phane%20vg/  
   
   .LINK  
     #http://msdn.microsoft.com/en-us/library/windows/desktop/aa376441(v=vs.85).aspx  
 #>       
        
      [cmdletBinding()]  
      Param (  
                [Parameter(Mandatory = $false, ValueFromPipeLine = $false)][ValidateSet("Alltypes", "TPM", "ExternalKey", "NumericPassword", "TPMAndPin", "TPMAndStartUpdKey", "TPMAndPinAndStartUpKey", "PublicKey", "PassPhrase", "TpmCertificate", "SID")]$KeyProtectorType  
      )  
        
      $BitLocker = Get-WmiObject -Namespace "Root\cimv2\Security\MicrosoftVolumeEncryption" -Class "Win32_EncryptableVolume"  
      switch ($KeyProtectorType) {  
           ("Alltypes") { $Value = "0" }  
           ("TPM") { $Value = "1" }  
           ("ExternalKey") { $Value = "2" }  
           ("NumericPassword") { $Value = "3" }  
           ("TPMAndPin") { $Value = "4" }  
           ("TPMAndStartUpdKey") { $Value = "5" }  
           ("TPMAndPinAndStartUpKey") { $Value = "6" }  
           ("PublicKey") { $Value = "7" }  
           ("PassPhrase") { $Value = "8" }  
           ("TpmCertificate") { $Value = "9" }  
           ("SID") { $Value = "10" }  
           default { $Value = "0" }  
      }  
      $Ids = $BitLocker.GetKeyProtectors($Value).volumekeyprotectorID  
      return $ids  
 }  
   
 function Get-ADBitlockerRecoveryKeys {  
 <#  
      .SYNOPSIS  
           Retrieve Active Directory Recovery Keys  
        
      .DESCRIPTION  
           Get a list of all bitlocker recovery keys in active directory.  
        
      .EXAMPLE  
           PS C:\> Get-ADBitlockerRecoveryKeys  
        
      .NOTES  
           Additional information about the function.  
 #>  
        
      [CmdletBinding()]  
      param ()  
        
      #Get Active Directory computer information  
      $ComputerName = $env:COMPUTERNAME  
      $ADComputer = Get-ADComputer -Filter { Name -eq $ComputerName }  
      #Get Bitlocker recovery keys  
      $ADBitLockerRecoveryKeys = Get-ADObject -Filter { objectclass -eq 'msFVE-RecoveryInformation' } -SearchBase $ADComputer.DistinguishedName -Properties 'msFVE-RecoveryPassword'  
      Return $ADBitLockerRecoveryKeys  
 }  
   
 function Get-BitlockerPassword {  
 <#  
      .SYNOPSIS  
           Get Bitlocker Password  
        
      .DESCRIPTION  
           Retrieve the bitlocker password of the specified protector ID  
        
      .PARAMETER ProtectorID  
           Key protector ID  
        
      .EXAMPLE  
           PS C:\> Get-BitlockerPassword -ProtectorID 'Value1'  
        
      .NOTES  
           Additional information about the function.  
 #>  
        
      [CmdletBinding()][OutputType([string])]  
      param  
      (  
           [ValidateNotNullOrEmpty()][string]$ProtectorID  
      )  
        
      $Password = manage-bde -protectors -get ($env:ProgramFiles).split("\")[0] -id $ProtectorID | Where-Object { $_.trim() -ne "" }  
      $Password = $Password[$Password.Length - 1].Trim()  
      Return $Password  
 }  
   
 function Initialize-HardwareInventory {  
 <#  
      .SYNOPSIS  
           Perform Hardware Inventory  
        
      .DESCRIPTION  
           Perform a hardware inventory via the SCCM client to report the WMI entry.  
        
 #>  
        
      [CmdletBinding()]  
      param ()  
        
      $Output = "Initiate SCCM Hardware Inventory....."  
      $SMSCli = [wmiclass] "\\localhost\root\ccm:SMS_Client"  
      $ErrCode = ($SMSCli.TriggerSchedule("{00000000-0000-0000-0000-000000000001}")).ReturnValue  
      If ($ErrCode -eq $null) {  
           $Output += "Success"  
      } else {  
           $Output += "Failed"  
      }  
      Write-Output $Output  
 }  
   
 function Invoke-ADBitlockerRecoveryPasswordCleanup {  
 <#  
      .SYNOPSIS  
           Cleanup Active Directory Bitlocker Recovery Passwords  
        
      .DESCRIPTION  
           This function will cleanup bitlocker recovery passwords that are no longer valid.  
        
      .PARAMETER LocalPassword  
           Bitlocker password of the local machine  
        
      .PARAMETER ADPassword  
           Bitlocker Passwords stored in active directory  
        
      .EXAMPLE  
           PS C:\> Invoke-ADBitlockerRecoveryPasswordCleanup  
        
      .NOTES  
           Additional information about the function.  
 #>  
        
      [CmdletBinding()]  
      param  
      (  
           [ValidateNotNullOrEmpty()][string]$LocalPassword,  
           [ValidateNotNullOrEmpty()]$ADPassword  
      )  
        
      foreach ($Password in $ADPassword) {  
           If ($LocalPassword -ne $Password.'msFVE-RecoveryPassword') {  
                Remove-ADObject -Identity $Password.DistinguishedName -Confirm:$false  
           }  
      }  
 }  
   
 function Invoke-EXE {  
 <#  
      .SYNOPSIS  
           Execute the executable  
        
      .DESCRIPTION  
           Execute the executable  
        
      .PARAMETER DisplayName  
           A description of the DisplayName parameter.  
        
      .PARAMETER Executable  
           A description of the Executable parameter.  
        
      .PARAMETER Switches  
           A description of the Switches parameter.  
        
      .NOTES  
           Additional information about the function.  
 #>  
        
      [CmdletBinding()]  
      param  
      (  
           [String]$DisplayName,  
           [String]$Executable,  
           [String]$Switches  
      )  
        
      Write-Host "Uploading"$DisplayName"....." -NoNewline  
      #Test if executable is present  
      If ((Test-Path $Executable) -eq $true) {  
           #Execute the executable  
           $ErrCode = (Start-Process -FilePath $Executable -ArgumentList $Switches -Wait -Passthru).ExitCode  
      } else {  
           $ErrCode = 1  
      }  
      If (($ErrCode -eq 0) -or ($ErrCode -eq 3010)) {  
           Write-Host "Success" -ForegroundColor Yellow  
      } else {  
           Write-Host "Failed with error code "$ErrCode -ForegroundColor Red  
      }  
 }  
   
 function New-WMIClass {  
 <#  
      .SYNOPSIS  
           Create New WMI Class  
        
      .DESCRIPTION  
           This will delete the specified WMI class if it already exists and create/recreate the class.  
        
      .PARAMETER Class  
           A description of the Class parameter.  
        
 #>  
        
      [CmdletBinding()]  
      param  
      (  
           [ValidateNotNullOrEmpty()][string]$Class  
      )  
        
      $WMITest = Get-WmiObject $Class -ErrorAction SilentlyContinue  
      If (($WMITest -ne "") -and ($WMITest -ne $null)) {  
           $Output = "Deleting " + $Class + " WMI class....."  
           Remove-WmiObject $Class  
           $WMITest = Get-WmiObject $Class -ErrorAction SilentlyContinue  
           If ($WMITest -eq $null) {  
                $Output += "Success"  
           } else {  
                $Output += "Failed"  
                Exit 1  
           }  
           Write-Output $Output  
      }  
      $Output = "Creating " + $Class + " WMI class....."  
      $newClass = New-Object System.Management.ManagementClass("root\cimv2", [string]::Empty, $null);  
      $newClass["__CLASS"] = $Class;  
      $newClass.Qualifiers.Add("Static", $true)  
      $newClass.Properties.Add("ADBackup", [System.Management.CimType]::Boolean, $false)  
      $newClass.Properties["ADBackup"].Qualifiers.Add("key", $true)  
      $newClass.Properties["ADBackup"].Qualifiers.Add("read", $true)  
      $newClass.Properties.Add("RecoveryPassword", [System.Management.CimType]::string, $false)  
      $newClass.Properties["RecoveryPassword"].Qualifiers.Add("key", $true)  
      $newClass.Properties["RecoveryPassword"].Qualifiers.Add("read", $true)  
      $newClass.Put() | Out-Null  
      $WMITest = Get-WmiObject $Class -ErrorAction SilentlyContinue  
      If ($WMITest -eq $null) {  
           $Output += "Success"  
      } else {  
           $Output += "Failed"  
           Exit 1  
      }  
      Write-Output $Output  
 }  
   
 function New-WMIInstance {  
 <#  
      .SYNOPSIS  
           Write new instance  
        
      .DESCRIPTION  
           Write a new instance reporting the last time the system was rebooted  
        
      .PARAMETER ADBackup  
           Boolean value specifying if the bitlocker recovery key is backed up to active directory  
        
      .PARAMETER Class  
           WMI Class  
        
      .PARAMETER RecoveryPassword  
           Bitlocker recovery password  
        
      .PARAMETER LastRebootTime  
           Date/time the system was last rebooted  
        
      .NOTES  
           Additional information about the function.  
 #>  
        
      [CmdletBinding()]  
      param  
      (  
           [ValidateNotNullOrEmpty()][boolean]$ADBackup,  
           [ValidateNotNullOrEmpty()][string]$Class,  
           [ValidateNotNullOrEmpty()][string]$RecoveryPassword  
      )  
        
      $Output = "Writing Bitlocker instance to" + [char]32 + $Class + [char]32 + "class....."  
      $Return = Set-WmiInstance -Class $Class -Arguments @{ ADBackup = $ADBackup; RecoveryPassword = $RecoveryPassword }  
      If ($Return -like "*" + $ADBackup + "*") {  
           $Output += "Success"  
      } else {  
           $Output += "Failed"  
      }  
      Write-Output $Output  
 }  
   
 function Publish-RecoveryPasswordToActiveDirectory {  
 <#  
      .SYNOPSIS  
           Publish Bitlocker Recovery Password  
        
      .DESCRIPTION  
           Publish Bitlocker recovery password to active directory.  
        
      .PARAMETER BitlockerID  
           Bitlocker Recovery ID that contains the Bitlocker recovery password  
        
      .EXAMPLE  
           PS C:\> Publish-RecoveryPasswordToActiveDirectory  
        
      .NOTES  
           Additional information about the function.  
 #>  
        
      [CmdletBinding()]  
      param  
      (  
           [ValidateNotNullOrEmpty()][string]$BitlockerID  
      )  
        
      #Define location of manage-bde.exe  
      $ManageBDE = $env:windir + "\System32\manage-bde.exe"  
      #Define the ManageBDE parameters to backup the Bitlocker recovery password to  
      $Switches = "-protectors -adbackup" + [char]32 + ($env:ProgramFiles).split("\")[0] + [char]32 + "-id" + [char]32 + $BitlockerID  
      Invoke-EXE -DisplayName "Backup Recovery Key to AD" -Executable $ManageBDE -Switches $Switches  
 }  
   
 function Remove-WMIClass {  
 <#  
      .SYNOPSIS  
           Delete WMIClass  
        
      .DESCRIPTION  
           Delete the WMI class from system  
        
      .PARAMETER Class  
           Name of WMI class to delete  
        
      .EXAMPLE  
                     PS C:\> Remove-WMIClass  
        
      .NOTES  
           Additional information about the function.  
 #>  
        
      [CmdletBinding()]  
      param  
      (  
           [ValidateNotNullOrEmpty()][string]$Class  
      )  
        
      $WMITest = Get-WmiObject $Class -ErrorAction SilentlyContinue  
      If (($WMITest -ne "") -and ($WMITest -ne $null)) {  
           $Output = "Deleting " + $Class + " WMI class....."  
           Remove-WmiObject $Class  
           $WMITest = Get-WmiObject $Class -ErrorAction SilentlyContinue  
           If ($WMITest -eq $null) {  
                $Output += "Success"  
           } else {  
                $Output += "Failed"  
                Exit 1  
           }  
           Write-Output $Output  
      }  
 }  
   
 Clear-Host  
 #Retrieve numerical password ID  
 [string]$BitlockerID = Get-BitLockerRecoveryKeyId -KeyProtectorType NumericPassword  
 #Retrieve Bitlocker recovery password from the local system  
 [string]$BitlockerPassword = Get-BitlockerPassword -ProtectorID $BitlockerID  
 #Backup bitlocker password to active directory is parameter is selected  
 If ($ActiveDirectory.IsPresent) {  
      #Retrieve the bitlocker recovery password(s) from active directory  
      $ADBitlockerPassword = Get-ADBitlockerRecoveryKeys  
      #Check if bitlocker password exists. If not, push to active directory  
      If ($ADBitlockerPassword -ne $null) {  
           #Check if it is a single password which the AD backup does not match the password on the system, or an array of passwords  
           If ((($ADBitlockerPassword -is [Microsoft.ActiveDirectory.Management.ADObject]) -and ($ADBitlockerPassword.'msFVE-RecoveryPassword' -ne $BitlockerPassword)) -or ($ADBitlockerPassword -isnot [Microsoft.ActiveDirectory.Management.ADObject])) {  
                #Delete all bitlocker recovery passwords that do not match the password on the local machine  
                Invoke-ADBitlockerRecoveryPasswordCleanup -LocalPassword $BitlockerPassword -ADPassword $ADBitlockerPassword  
                #Get the password stored in AD after the cleanup  
                $ADBitlockerPassword = Get-ADBitlockerRecoveryKeys  
                #If the AD password does not exist, or does not match the local password, publish the new AD Bitlocker password  
                If (($ADBitlockerPassword.'msFVE-RecoveryPassword' -ne $BitlockerPassword) -or ($ADBitlockerPassword -eq $null)) {  
                     #Push the local bitlocker password to AD  
                     Publish-RecoveryPasswordToActiveDirectory -BitlockerID $BitlockerID  
                     #Retrieve the bitlocker recovery password from active directory  
                     $ADBitlockerPassword = $null  
                     $Count = 1  
                     #Wait until the bitlocker password is in active directory  
                     Do {  
                          $ADBitlockerPassword = Get-ADBitlockerRecoveryKeys  
                          Start-Sleep -Seconds 1  
                          $Count += 1  
                     } while (($ADBitlockerPassword -eq $null) -or ($Count -lt 30))  
                }  
           }  
      } else {  
           Publish-RecoveryPasswordToActiveDirectory -BitlockerID $BitlockerID  
           #Retrieve the bitlocker recovery password from active directory  
           $ADBitlockerPassword = $null  
           $Count = 1  
           #Wait until the bitlocker password is in active directory  
           Do {  
                $ADBitlockerPassword = Get-ADBitlockerRecoveryKeys  
                Start-Sleep -Seconds 1  
                $Count += 1  
           } while (($ADBitlockerPassword -eq $null) -and ($Count -lt 30))  
      }  
 }  
 #Publish data to SCCM  
 If ($SCCMReporting.IsPresent) {  
      New-WMIClass -Class Bitlocker_Reporting  
      If ($ADBitlockerPassword.'msFVE-RecoveryPassword' -eq $BitlockerPassword) {  
           If ($SCCMBitlockerPassword.IsPresent) {  
                New-WMIInstance -ADBackup $true -Class Bitlocker_Reporting -RecoveryPassword $BitlockerPassword  
           } else {  
                New-WMIInstance -ADBackup $true -Class Bitlocker_Reporting -RecoveryPassword " "  
           }  
      } else {  
           If ($SCCMBitlockerPassword.IsPresent) {  
                New-WMIInstance -ADBackup $false -Class Bitlocker_Reporting -RecoveryPassword $BitlockerPassword  
           } else {  
                New-WMIInstance -ADBackup $false -Class Bitlocker_Reporting -RecoveryPassword " "  
           }  
      }  
      #Initialize SCCM hardware inventory to force a reporting of the Bitlocker_Reporting class to SCCM  
      Initialize-HardwareInventory  
 } else {  
      Remove-WMIClass -Class Bitlocker_Reporting  
 }  
 #Publish data to Network Share  
 If ($NetworkShare.IsPresent) {  
      #Test if the $NetworkSharePath is defined and available  
      If ((Test-Path $NetworkSharePath) -eq $true) {  
           #Define the file to write the recovery key to  
           If ($NetworkSharePath[$NetworkSharePath.Length - 1] -ne "\") {  
                $File = $NetworkSharePath + "\" + $env:COMPUTERNAME + ".txt"  
           } else {  
                $File = $NetworkSharePath + $env:COMPUTERNAME + ".txt"  
           }  
           #Delete the file containing the recovery key if it exists  
           If ((Test-Path $File) -eq $true) {  
                $Output = "Deleting $env:COMPUTERNAME.txt file....."  
                Remove-Item -Path $File -Force  
                If ((Test-Path $File) -eq $false) {  
                     $Output += "Success"  
                } else {  
                     $Output += "Failed"  
                }  
                Write-Output $Output  
           }  
           #Create new text file  
           If ((Test-Path $File) -eq $false) {  
                $Output = "Creating $env:COMPUTERNAME.txt file....."  
                New-Item -Path $File -ItemType File -Force | Out-Null  
                If ((Test-Path $File) -eq $true) {  
                     Add-Content -Path $File -Value $BitlockerPassword  
                     $Output += "Success"  
                } else {  
                     $Output += "Failed"  
                }  
                Write-Output $Output  
           }  
      }  
 }  
 #Display output to the screen  
 Write-Output " "  
 $Output = "         Bitlocker ID: " + $BitlockerID  
 Write-Output $Output  
 $Output = "  Bitlocker Recovery Password: " + $BitlockerPassword  
 Write-Output $Output  
 $Output = "AD Bitlocker Recovery Password: " + $ADBitlockerPassword.'msFVE-RecoveryPassword' + [char]13  
 Write-Output $Output  
   

About Mick Pletcher

My blog is here to help solve issues I have encountered and solved, publish scripts I have written, and educate others in understanding areas that are not well covered

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