Powershell script to delete computer account from active directory and remove the computer object from SCCM. Threw this together after having to delete/remove 10+ computers in a single sitting. Much quicker than using the GUI.

    Deletes computer from SCCM and AD
    Queries AD & SCCM, deletes the computer account from AD, and removes the computer object from SCCM 
    Author: Jonathan - [email protected] 
.PARAMETER computerName
	Name of computer to delete from AD/SCCM
.PARAMETER sccmServer
	Name of the SCCM server to use
	Name of the SCCM site to use
	.\delcomp-adsccm.ps1 -computerName CON-01337
	.\delcomp-adsccm.ps1 -computerName CON-01337 -sccmServer sccm.contoso.com
	.\delcomp-adsccm.ps1 -computerName CON-01337 -sccmServer sccm.contoso.comm -sccmSite YOURSITE

param (
	[parameter(Mandatory=$true, HelpMessage="Enter a computer name")][string]$computerName,
	[parameter(Mandatory=$false, HelpMessage="Enter SCCM server")][string]$sccmServer='sccm-server.contoso.com',
	[parameter(Mandatory=$false, HelpMessage="Enter SCCM server")][string]$sccmSite='YOURSITE'

# find and delete the computer from AD
$dom = [System.DirectoryServices.ActiveDirectory.Domain]::GetCurrentDomain()
$root = $dom.GetDirectoryEntry()
$search = [System.DirectoryServices.DirectorySearcher]$root
$search.filter = "(&(objectclass=computer)(name=$computerName))"
$search.findall() | %{$_.GetDirectoryEntry() } | %{$_.DeleteObject(0)}

# find and delete from SCCM
$comp = get-wmiobject -query "select * from SMS_R_SYSTEM WHERE Name='$computerName'" -computername $sccmServer -namespace "ROOT\SMS\site_$sccmSite"

# spit out results
Write-Host "Deleted $computerName from AD. Removed $computerName from SCCM server $sccmServer, site $sccmSite"