I have been playing the game for a long time now and have not discovered an issue up until this point.
I have a number of mods installed including:
Airplane plus, BD armoury, KAS, KIS, Module manager and Kerbal Konstructs.
The problem is when I enter the astronaut complex, I am not able to leave. Everything else in the game runs perfectly fine but once I enter the Astronaut complex, I cannot leave.
If anyone is able to help me I would very much appreciate it. I have tried to look this problem up on the forum but have not been able to find anything relevant yet.