All users working are in the Editor writing queries. Users will connect to the db, and run a query, without an end user actually initiating a query. This has happened when opening a toad file; it will kick off and connect before users run anything. We had a staff member leave toad open one evening. Our DBA had to kill this query Every time it was killed, it would start back up on its own.
Other times, it will run only a portion of the query. This would cause an issue. Without the full code, TDP is running an extremely extensive search (i.e., pulling data from a table with millions of records).
Users have to keep killing the connection to the database, and reconnecting to continually stop these active processes that do not show up in the 'View Background Processes' activity.
Out of date SQL server 2008 (64 bit).
Confirm that the SQL server 2008 is up to date with the current update.