Math mentioned this before. Ill tell you the same thing I told him
It happens a lot, usually when games get crowded, when chats get full...
Also, with L2 you can play multiple games, therefore you have more data being processed at any given time. The session conflict seems to work as a preventative measure for crashes. The game could crash sometimes when you open it, or it can crash less often but with a session conflict message. I brought this up as one of the suggested bug fixes for the update, should be simple and cheap but very effective and a priority.
A wise guy's always right; even when he's wrong he's right
-Lefty, Donnie Brasco
400th Page TPBM