Indeed it is the PMDG744 and the module creating that problem is the PMDGoptions.dll (I think this is the name).There are several topics in the PMDG forums talking about this and the PMDG guys promised they will address this problem in an upcoming patch.So far, the only way of avoiding this problem is to switch ACs, loading the PMDG744 before exiting.Leo

I don't have AC and I do have the same problem...that started right after I installed the 744. It is the 744 module mentioned above that creates this problem.Leo

FS9 restarting is due to the checkbox on the error dialog. It gives the option of restarting the sim. Just uncheck it before closing the error dialog.Don't know why it gives the error on exit.

You might try using Cntrl. + C and see if that exits the sim without an error. It's the default instant exit command.

You have to love these boards. I've been having the same problem and thought I was going to have to spend a few hours, or more, going back through what I've installed lately to find the culprit, if in fact it was even an FS9 issue. After reading this, I can just sit back, click on "don't restart fs9" when the error message comes up, and wait for the patch. Thank you Avsim!billg