This project is currently in use by another user and is locked

The DGW client crashed with a project open and now when I try to open the project I get the following message:

This project is currently in use by another user and is locked

You cannot use this project until the lock is released

No other users are using the project and I have restarted my machine.

Subject: RE: This project is currently in use by another user and is locked

You might have better luck getting an answer to this here: IBM Support