Every time I try to approach the entrance to Diamond City, Piper and everybody else immediately attacks me. I may have killed a Diamond City guard earlier in the piece after they fired on me, but not close to Diamond City itself. The turrets don't open up on me until the guards do, so I'm a bit confused.

Are you wearing power armor with the highlight living mod on the helm?

Thanks Sunnie, I'm not wearing any power armour, just random body armour picked up along the way.

I have now gone back to an older saved game, lost about fifty minutes of play, and tried again, and this time got in no trouble at all! So I guess I must have killed the wrong person on my way to the location.