I have read almost all of the post on how to uninstall exchange 2010. I think I need to uninstall arbitration mailboxes directly through ADSIEdit.msc. How do I identify these mailboxes if I am unable to get into the PowerShell management console or the GUI management console? Thanks!

They have standard aliases: Alias : SystemMailbox{e0dc1c29-89c3-4034-b678-e6c29d823ed9} Alias : FederatedEmail.4c1f4d8b-8179-4148-93bf-00a95fa1e042 The other will have a unique alias, but will start with SystemMailbox as well with a display name of Microsoft Exchange Approval Assistant. Be sure not to delete any production system maiulbox that may be linked to other Exchange Servers. Alternatively, install just the mgmt tools on another server/workstation and remove via powershell from there.