Powershell - Current User Registry

$root = [Microsoft.Win32.RegistryHive]::Users
$regKey = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey($root, $ComputerName)

# Get all SIDs that don't end with _Classes and are 
# long enough to be a domain SID (not local machine).
$users = $regKey.GetSubKeyNames() | where { $_.Length -gt 10 -and $_.EndsWith("_Classes") -eq $false }  

foreach ($usersid in $users)
{
	# Open the key for write access
	$key = "$usersid\SOFTWARE\Microsoft"  
	$regKey = $regKey.OpenSubKey($key, $true)
	$regKey.SetValue("A Test Value", "a meaningless string", 'String')  
}

Es ist nicht möglich, eine Methode für einen Ausdruck aufzurufen, der den NULL hat.
In Zeile:8 Zeichen:2
+     $regKey.SetValue("A Test Value", "a meaningless string", 'String' ...  
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) , RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull