|I've never had a PC 'accidentaly' change itself from workgroup to domain. Someone would have to make that change.|
The place to look is in System Properties
Open it up (Control Panel >> System) and click on the "Computer Name" tab. If it is indeed in a domain and not a workgroup, you can change it back to workgroup by clicking on the "Change" button.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.