Weird ComboBox error

Question

Hey
I have a really weird problem. I use 2 ComboBox's that are data bound (each has it's own database, both databases are independent and have no similar columns). Everything is working perfectly until I try to close my application. When the Close() method is triggered it doesn't close the application, but rather cuts the connection to the data sources (Or at least I think so), both ComboBox's loose all their items and only on the second click does it close the application. If I run the application again, everything works properly. This is a really weird situation, I really never heard or seen something like this. Does anyone know what the problem is?