The Work Arounds listed below in the dev quote don't work at all for me because the options keep getting changed back to default when I click ok. Leaving me completely unable to change anything in my Options or other windows.
Originally Posted by StormShade
Most mission instances are max 5 players - always have been. That is the way the game is designed. Larger sector maps, pvp maps, social maps have higher player limits.
The BUG you are seeing right now is that so many people are trying to access the same mission that it is filling up the 5 player maps before you client realizes. It attempts to transfer you to a map and when it cannot, it pulls up a map list - something you will rarely ever see unless the map you requested was full by the time you got there.
We are addressing this BUG in the next patch.
For now, you can go to Options, HUD, and deselect ALWAYS SHOW INSTANCE MAP LIST which should help a little bit.
Please relax. Have some patience. We are fixing bugs non stop here in the office. We'll get the fixes out to you as fast as the builder can make the patch and post it to the server.
ANOTHER solution is to go into SOCIAL menu and deselect Auto Grouping by default. This will place you on your own map.