Minute I enter the Fort Dawnguard zone the first few npc's attack me and when I enter the actual fort the leader of dawnguard is also instantly hostile so I cannot continue the quest anyone else having this problem?

I didn't have this problem.

Are you currently a vampire or do you have a bounty in the Rift?

Definetly not a vampire and no bounty that I know of, it definetly seems like a bug because they start talking to me at first and after a sentence or two pull out their weapons and just start to attack me.

Maybe getting a bounty in the area and clearing it might solve the problem? I'm not sure how likely that is to fix it but I'd say it's worth the effort.

I have the same problem and I am even getting attacked outside the entrance to the cave to go to the fort by vigilants of stendarr. I have no bounty in the rift either and am not a vampire as I am a werewolf. Also reloading does not work nor have I had this problem before.

I'm in the same boat, I bought this $20 game and i can't even start to play it. Does Bethesda even go over its products at all? They had better fix it soon or they're gong to lose a customer. Not that they care.

Try clearing your bounty then going in and out of some places, i tryed it and it works normally now

Bump. I've tried clearing my system cache and going in and out of dayspring cavern before going to the first guy. He ran while talking for a while then turned around in view of the castle and attacked. Last time he attacked it was immediate.

Yeah, I had the same issue with ft dawnguard. I got a bounty then paid it off and that did the trick.

This happened to me as well, but I was able to fix it. I made a thread about it here.

http://www.gamesas.com/topic/1390415-everything-suddenly-become-hostile-in-your-game-fix-here/