Hello Crazyjames,
When you try to press the F4 button, what happens? Also have you tried any other games to make sure that your F4 button actually works?
Does this only happen on the DarkRP server,
do i have to accept any rules or something in the game?
No you don't, once you join you're simply ingame.
Please answer some of theese questions so we can assist you better!
Dear regards,
Optec