It's vague on purpose, but, *maybe spoilers* just in case.

Sorry if this has been discussed already but...

I need to deliver a letter to Doctor somebody, but when I go searching for him in the building the NCR starts shooting at me. My gun was holstered, so not sure what happened. I've got a neutral rep with them and I wind up getting shunned by Crimson.

What happened?!

Were you wearing someone else's uniform? like powder gangs or something?

or did you accidently steal something? I had that happened to me when I ransacked a nuka-cola machine on reflex.

No, just the caravan leather armor that came with the pre-order. Didn't steal a thing, well, not there anyways.

My problem was that I couldn't actually find the bastard? Is it a glitch that doesn't update the map marker on this quest, or was that intentional? I've tried going back to the executive-whats-her-face at the Caravan's office and she doesn't even acknowledge I'm doing a quest for her.

Oh, I found him, but it was after the entire building decided to open fire. He was doing the duck and run thing. Talked to me just fine after I killed everyone.

...Where was he?

The guy you have to meet is on the bottom floor behind the stairs. Follow the arrow but dont go up the stairs go behind the stairs and then go right after you go behind em. Also the reason the NCR guys are shooting at you is because you are not allowed on the tram unless you have a NCR uniform.