I just migrated my old minecraft account to a mojang account and the first thing I did was change my name. I went to the mojang website, found my profile, my username and hit change. I typed my new name and it went through. I launched minecraft to find that I still had my old username. Curious, I tried to join a server which I knew was working. I got the error message: not authenticated with minecraft.net . In case you were wondering, I had launched this same server the day before and it worked flawlessly. This is now the 2nd day I've had this issue, with no solutions on the minecraft troubleshooting page. I am launching it from the standard launcher, which I installed on my linux profile 3 days ago, if that makes any difference. If anybody knows what's happening here and can offer a solution, I would be very grateful.