When I start, Eclipse says "Workspace Cannot Be Locked"
"Could not launch the product because the associated workspace is currently in use by another Eclipse application." or “Workspace in use or cannot be created, chose a different one.”
But I know it isn't.
How do I "unlock" it?
Just delete the .lock file in the .metadata directory in your eclipse workspace directory.
Precaution - If you delete the .metadata folder all preference will be deleted.