This has becoming a problem for me recently. Sometimes when I alt+tab, the game quickly closes without any sort or warning or error. This isn't a huge problem, and it has been addressed several times as likely an "outdated driver" problem.

The main problem is when I try to get back online. The game thinks I'm still online and my Spiral Knights crashes whenever I log into the same account. If I'm running with my friends, they tell me through Skype that my character was standing still in the dungeon I disconnected from and I was on their friend list. Every time this happens, I have to wait out the inactivity timer and I have to restart the whole dungeon. Possibly worse, any party I'm with has to either kick me or all go solo-losing most of the party member's drops.

Does anyone know a way to prevent this or a way to let the game know you're offline?