Preston garvey will not talk to me since I dissmissed him to get piper, He just click him and he says nothing just that static sound when I click him. I need to turn in a quest to him but he just will not talk.

I'm getting a similar problem in bugged NPC's for the Danger Minds quest which I posted about http://www.gamesas.com/topic/1548464-main-quest-dangerous-minds-is-bugged/

No response from anyone but it's completely game-breaking since it's the main quest. It's also now affecting a side quest that I was trying to complete with Kent at the dream place.

Is this where we're supposed to go for support? I haven't seen Bethesda respond to anyone...

I cannot progress the minute man story, Beth should fix these those.

I arrived in good neighbour and neither of the 2 vendors near the entrance (the robot and the ghoul) will sell to me. When I click them I get their random line of dialogue and then nothing else - no dialogue menu to select barter from, etc. If I try clicking while they are talking the dialogue will not skip either. I had a similar issue with a wandering vendor outside diamond city at the start of the game but just thought at the time that she was not able to sell to me yet and it might be settlement related (seems it wasn't and the bug stems back to my early hours of play).

I have re-zoned, passed huge amounts of time, gone back a few saves, tried using vendors elsewhere and coming back but nothing fixes it.

I also have a strange issue where some of the generic NPCs in diamond city have stopped talking, they just stand there with their arms outstretched to the sides and do nothing at all, not possible to have dialogue with them or anything.