Start with a Shutdown/restart of your computer. If you're on a network, you might disconnect your network just to be sure nobody else is trying to gain access to your database.
When the computer restarts, if any LDB files (Access Lock-file) exist related to your database, delete them.
When you open the database (and if you have not disabled the shift key) hold down one of the Shift keys on your keyboard until the database is fully opened (until you see the Database window). This will prevent any startup options from running.
Assuming your database will open... Don't know what Jetcomp is. But there is an option in Access to Compact and Repair under Tools | Database Utilities. Maybe Jetcomp runs that? But I would try running the Access Compact and Repair just to be sure.
If your database doesn't open, try creating a new database and importing each object from the one you can't open. This may not be possible if the old database is still locked.
If all of that doesn't work, try running Access's "Detect and Repair" from the Help menu then repeat the prior steps.
If all of that doesn't work, let us know. I can't think of anything else right now. But someone else may have more ideas.
Randall J Weers
Membership Vice President
Pacific NorthWest Access Developers Group