We have several machines that are used by developers that won't launch teams anymore. I have verified it happens under a different profile so it doesn't appear to be a corrupt profile issue. I have tried to reinstall it and that doesn't launch correctly either. I don't really see anything useful in event viewer to tell me why it isn't launching correctly.
The only similarity that I can think of is these users have Visual Studio installed but there are users with Visual Studio installed and it works fine.