I've recently had an issue with the NCR attacking me for no reason. I'm not killed a single member of NCR, I'm not wearing any other groups costume and I've not done anything else that would cause them to attack me.

I have killed Caesar and Mr House but I had no message about my NCR rep. I also crept in to (Wearing an NCR costume) Camp McCarren and finished 3 Card Bounty and Three Stands the Grass to get the positive rep. As soon as I changed back to Combat Armor, NCR started attacking me again.

I have read on http://forums.steampowered.com/forums/showthread.php?t=1539019 that changing to certain costumes and back, will permanently change your appearance to the NCR, although they're playing the PC version rather than the 360 one. Any help would be much appreciated.

I had the same problem right after I did the Brotherhood of Steel quests and instead of wearing the armor they gave me i used their armor which made me dressed as one of them and even though before i went back to the vegas strip i put on my combat armor the NCR saw me as a traitor and all of them attacked me so now I had to go to a save way before i finished the brotherhood quests...... they mustve only done a quick run through when they tested this game cause this isnt the first glitch ive found and i have under 24 hours of play time