Powser Shell Script to Purge Computer Records from SCCM

Question

Hello!
I have built a collection in Configuration Manager to bring in a list of computers that have duplicate names. Here is the query that I am using.
select R.ResourceID,R.ResourceType,R.Name,R.SMSUniqueIdentifier,R.ResourceDomainORWorkgroup,R.Client from SMS_R_System as r   full join
SMS_R_System as s1 on s1.ResourceId = r.ResourceId   full join SMS_R_System as s2 on s2.Name = s1.Name   where s1.Name = s2.Name and s1.ResourceId != s2.ResourceId
I am building a PowerShell Script to obtain the names of the computer resources stored in the above SCCM 2012 collection and place them in a variable. Next,
I want to obtain the computer resources (e.g., ddr records) and store them in a 2ed variable using the first variable to pipe in the data. I am using a “ForEach” looping construct to accomplish this. Lastly, I want to purge the computers records from the Configuration
Manager database that are stored in the second variable which came from the computers names of the specified SCCM collection. I am attempting to use this line of code within my loop to purge the computer records from SCCM:
$compObject.psbase.syncroot | % { $_.psbase.delete()
Here is a
blog I found suggesting this line of code.
What I have discovered is rather interesting. My script works as intended, but even though the correct records  ARE
being purged. The above line of code is returning an error.
You cannot call a method on a null-valued expression.
At line:18 char:35 + $compObject.psbase.syncroot | % { $_.psbase.delete() }
+                                   ~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull
I have a few questions:
Does anyone know why this is occurring?
Is there a different approach or code I should be using instead to purge the collected data?
Here is my full script:
#// required parameters
$SCCMServer
= "MySiteServer"
$sitename
= "PS1"
$collectionID
= "PS1009c8"
#// Obtain collection members from $collectionID
$SMSClients
= Get-WmiObject
-Query "SELECT * FROM SMS_FullCollectionMembership WHERE CollectionID='$collectionID' order by name" 
-ComputerName $SCCMServer
-Namespace  "ROOT\SMS\site_$sitename"
#//looping construct to loop through all the colection members
ForEach ($SMSclient
in $SMSclients) {
#// Loads computer records one at a time into $compobject variable using a ForEachloop to be deleted
$compObject
= get-wmiobject
-query "select * from SMS_R_SYSTEM WHERE Name='$($smsclient.name)'"
-computername $SCCMServer
-namespace "ROOT\SMS\site_$sitename"
#// Delete’s computer objects one at a time in $compObject variable from CM12 database
$compObject.psbase.syncroot
| % {
$_.psbase.delete() }
--Tony

Answer 1

Daniel
Have you ever used Orchestrator to kick off your Powershell scripts? I am using System Center 2012 R2 Orchestrator, and trying to use the "Run .Net Script" action to launch my Powershell code, but the process is failing.  When I run the code
from within PowerShell and RunBook Tester the code executes as it should. When I run it from the RunBook I receive this error:
Exception calling "Delete" with "0" argument(s): "Generic failure "
Just curious if you had any thoughts why my code was blowing up in an Orchestrator RunBook when it works fine within PowerShell? My full code is below.
#// required parameters
$SCCMServer = "MySiteServer"
$sitename = "PS1"
$collectionID = "PS1009c8"
#// Obtain collection members from $collectionID
$SMSClients = Get-WmiObject -Query "SELECT * FROM SMS_FullCollectionMembership WHERE CollectionID='$collectionID' order by name" -ComputerName $SCCMServer -Namespace "ROOT\SMS\site_$sitename"
#//looping construct to loop through all the colection members
ForEach ($SMSclient in $SMSclients) {
#// Obtains and deletes the SCCM computer records one at a time using a ForEachloop
Get-WmiObject -query "select * from SMS_R_SYSTEM WHERE Name='$($smsclient.name)'" -computername $SCCMServer -namespace "ROOT\SMS\site_$sitename" |
ForEach-Object { $_.Delete() }