Retrieve your SharePoint Product key from server [2007 / 2010 / 2013]

based on http://jk-point.blogspot.co.il/2013/03/retrive-your-sharepoint-product-key.html

PowerShell Script to Recover SharePoint 2007 Product key:

function Get-SP2007ProductKey {   
    $map="BCDFGHJKMPQRTVWXY2346789"
    $value = (get-itemproperty "HKLM:\SOFTWARE\Microsoft\Office\12.0\Registration\{90120000-110D-0000-1000-0000000FF1CE}").digitalproductid[0x34..0x42] 
    $ProductKey = "" 
    for ($i = 24; $i -ge 0; $i--) {
      $r = 0
      for ($j = 14; $j -ge 0; $j--) {
        $r = ($r * 256) -bxor $value[$j]
        $value[$j] = [math]::Floor([double]($r/24))
        $r = $r % 24
      }
      $ProductKey = $map[$r] + $ProductKey
      if (($i % 5) -eq 0 -and $i -ne 0) {
        $ProductKey = "-" + $ProductKey
      }
    }
    $ProductKey
}

#Call the function

Get-SP2007ProductKey

PowerShell Script to Recover SharePoint 2010 Product Key:

function Get-SP2010ProductKey {   
    $map="BCDFGHJKMPQRTVWXY2346789"
    $value = (get-itemproperty "HKLM:\SOFTWARE\Microsoft\Office\14.0\Registration\{90140000-110D-0000-1000-0000000FF1CE}").digitalproductid[0x34..0x42] 
    $ProductKey = "" 
    for ($i = 24; $i -ge 0; $i--) {
      $r = 0
      for ($j = 14; $j -ge 0; $j--) {
        $r = ($r * 256) -bxor $value[$j]
        $value[$j] = [math]::Floor([double]($r/24))
        $r = $r % 24
      }
      $ProductKey = $map[$r] + $ProductKey
      if (($i % 5) -eq 0 -and $i -ne 0) {
        $ProductKey = "-" + $ProductKey
      }
    }
    $ProductKey
}
#Call the function
Get-SP2010ProductKey

And here's the code for Sharepoint 2013

function Get-SP2013ProductKey { 
$map="BCDFGHJKMPQRTVWXY2346789" 
$value = (get-itemproperty "HKLM:\SOFTWARE\Microsoft\Office\15.0\Registration\{90150000-110D-0000-1000-0000000FF1CE}").digitalproductid[0x34..0x42] 
$ProductKey = "" 
for ($i = 24; $i -ge 0; $i--) { 
$r = 0 
for ($j = 14; $j -ge 0; $j--) { 
$r = ($r * 256) -bxor $value[$j] 
$value[$j] = [math]::Floor([double]($r/24)) 
$r = $r % 24 
} 
$ProductKey = $map[$r] + $ProductKey 
if (($i % 5) -eq 0 -and $i -ne 0) { 
$ProductKey = "-" + $ProductKey 
} 
} 
$ProductKey
} 
#Call the function
Get-SP2013ProductKey