Game crashes while booting

I were playing finely, until the game started to crash while booting today.
I have windows 7, and I disabled Avast scanning thingy (?) for it.
I think that I am running the latest version, not sure.

Hey,

I would suggest reading this thread;

http://forum.greenheartgames.com/t/solutions-anti-virus-false-positives-eg-avast-norton-bitdefender/6124/

and then reinstalling Game Dev Tycoon after you have created the exception. If you redownload the game from the original fastspring email and install that fresh copy you will be guaranteed to have the most up to date version.
This will also restore file integrity.