Ghost 14.0 Error E4BC0012 in middle of My Documents backup-- database locked

Running Ghost 14.0.  While running a My Documents backup I got the following Error Message:

"An interaction with the catalog's database layer failed unexpectedly: sqlite3_step-5: Database is locked."

The backup failed.

Help!  how can I "un-lock" the database or otherwise work around this?

Running Windows XP SP3.

Thanx,

Don