That time of year again (well - for us anyway), after doing a load of machine rebuilds - and name changes etc - your AD may look a bit cluttered. Even more so as we moved from using RIS (groan - old tech alert) to SCCM...

So - rather than resurrect some old threads, here is a collection of highly useful powershell scripts to hunt out those old computers and remove them or move them to another OU so you can spot them all together.

Credit to original posters: Boz_l and Rabbieburns

For this, you will need to install and run the Quest Powershell console.

Quest AD Cmdlets are free to download from PowerShell Commands (CMDLETs) for Active Directory by Quest Software

GOTCHA: these commands do not seem to run in the standard shell even with the cmdlets installed. A bit like exchange 2010 seems to need its own shell.

Outputs to shell console:

get-qadcomputer -IncludeAllProperties | Where-Object { $_.lastlogon -lt (get-date).AddDays(-90) } 

Outputs to csv:

get-qadcomputer -IncludeAllProperties | Where-Object { $_.lastlogon -lt (get-date).AddDays(-90) } | select-object Name, ParentContainer, Description, pwdLastSet | export-csv c:\outdated.csv

Moves to alternate OU:

get-qadcomputer -IncludeAllProperties | Where-Object { $_.lastlogon -lt (get-date).AddDays(-90) } | Move-QADObject -to my.corp/obsolete 

Tack this to the end to disable the accounts:

| disable-QADComputer

Check Locate obsolete computer records in AD « Dmitry’s PowerBlog: PowerShell and beyond for more.

And QAD cmdlets reference - PowerGUI Wiki

Enjoy :-)