Seats And Vehicles Are Not Working.

Sorry if i’ve put this in the wrong place, or if there’s already a thread like this etc.
Whenever i create a singleplayer game on sandbox, it will only let me either enter a single vehicle once, or not at all. If i use a jeep, the engine comes on, and the handbrake comes off, allowing it to freewheel, but i can’t actually get in.
Im certain it can’t be a hardware problem, and i have more or less every usefull addon under the sun.(yes that’s probably the cause)
I don’t want to reinstall because i’d probably copy the addons to the new install and cause the problem again.
So i was wondering, does anyone know of any addons that could cause this?
Also if i create a game on rp (meaning that you can enter vehicles that don’t belong to you) i can get into the seats and such, but this isn’t especially handy seeing as you can’t R your massive contraptions. Seats also work if i join my dedicated server that’s on sandbox.
Thanks for any help!

Your addons broke it. Plain and simple.

I’d established that.
but thanks anyway