Hey all. I know this topic is old but wanted to add a note for anyone else who is in the position I was in with this CTD issue. There was nothing useful in the logs and the 300 and 400 models were both crashing for me instantly. I usually fly the CS B733 regularly but then I remembered I hadn't used the since I upgraded the CPU in my machine a couple of weeks back. I don't know if CS do a install-check and fail if it looks like the install has been pirated but maybe they do. Turns out after re-installing the base model the aircraft starts up fine, so all good for me now. Hope this helps.