Powershell 2.0 how to get the values from remote registry "\..\WindowsUpdate\Auto Update\RebootRequired"

I am trying to query a registry path of a remote server:

"HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\Auto Update\RebootRequired"

This contains a list of all updates that are pending a reboot (REG_DWORD), and perhaps some dates of some kind. I am interested in the number of pending updates only.

Performing the following PS cmdlet, I do not get the result I expect in querying the reg path:

       $Computer = "Server01" 
       $HKLM = [UInt32] "0x80000002" 
       $WMI_Reg = [WMIClass] “\\$Computer\root\default:StdRegProv” 
       $RegRR = $WMI_Reg.EnumKey($HKLM,"SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\Auto Update\RebootRequired")

$RegRR = 
__GENUS          : 2
__CLASS          : __PARAMETERS
__SUPERCLASS     : 
__DYNASTY        : __PARAMETERS
__RELPATH        : 
__PROPERTY_COUNT : 2
__DERIVATION     : {}
__SERVER         : 
__NAMESPACE      : 
__PATH           : 
ReturnValue      : 0
sNames           : 

However, as a test, if I query the path one key before this, excluding "\RebootRequired" then this works and I can then query the sValues.

$RegRR = $WMI_Reg.EnumKey($HKLM,"SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\Auto Update\

__GENUS          : 2
__CLASS          : __PARAMETERS
__SUPERCLASS     : 
__DYNASTY        : __PARAMETERS
__RELPATH        : 
__PROPERTY_COUNT : 2
__DERIVATION     : {}
__SERVER         : 
__NAMESPACE      : 
__PATH           : 
ReturnValue      : 0
sNames           : {Power, RequestedAppCategories, Results, RebootRequired...}

Ultimately, I wish to query this reg key in order to return back the number of updates pending a reboot, existing DWORD records. There is a RebootRequiredSince date, which at first could be useful, but found out that not all of our servers have this (mix of 2008 R2 and 2012).

Any ideas?

Thanks

Make sure you enable the RemoteRegistry Service on the target machine, then you can try:

$Computer = "RemoteComputerName"
$RootKey = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey("LocalMachine",$Computer)
$SubKey = $RootKey.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\WindowsUpdate\\Auto Update\\RebootRequired")

To get all the available values you can do:

$SubKey.GetValueNames()

To get all the Subkey Names:

$SubKey.GetSubKeyNames()

To get Specific value:

$SubKey.GetValue("ValueName")

To Get the Default Key Value:

$SubKey.GetValue($null)