FS9 Lockup after installing upgrade

After removing PMDG with remove tool and installing upgrade I am getting two errors. When I open FS9, within a few seconds, I get the following error: "Aircraft initialization error. B737-7H4 Southwest Airlines Classic." After this, FS9 locks up on the opening screen with the error "Microsoft Flight Simulator has encountered a problem and needs to close. Sorry for the inconvenience." I never get past the opening screen.I thought I removed the SWA liveries that I had installed. I have tried removing and reinstalling the upgrade several times.Anyone have any ideas?? I hope I don't have to reinstall FS9.I am also using FSNavigator, RC3, SoCal MegaScenery. Didn't have any problems with PMDG before.BTW, now, after using the remove tool and trying to open FS9 (without reinstalling upgrade), I get the same errors. In essence, FS9 is currently dead in the water.Thanks for any help,Don Maxwell