Game Client Lost its connection to server
Error code 7 is a typical error code for a disconnect. Here are some tips from Anet (it recommends port forwarding, but I personally use QoS, this has also helped with my lag significantly.
https://en.support.guildwars2.com/app/answers/detail/a_id/8994/~error-codes
You may also test this when you are having huge lag issues:
https://en.support.guildwars2.com/app/answers/detail/a_id/9245/kw/Lag
It sometimes helps to determine the cause.
However, there have been reports from many players that code 7 has been occurring more frequently starting after the last minor patch this past week. I personally have not been disconnected, but had started experiencing extreme lag and input lag. Others reported this concurrently also. Mine cleared up roughly Wednesday night (Pacific time US), but is still occurring sporadically.
Try those steps, if you can’t stay connected, check the tech support forum for the sticky on submitting a ticket and then do so.
+ Also, be certain any and all firewalls, virus scanners, or port blockers are temporarily disabled to test if that is the cause sometimes, even modems/routers sometimes have them enabled by default and need exceptions made. Windows firewall is notorious for that stuff too, I think 64bit windows needs 2 exceptions for guild wars2.