There is a larger thread on this with literally 100s of players stating this issue. I myself was having the same problem, twice a day, during the major server errors (1017). I would get booted, and be unable to log in for days due to server congestion.

It went away when I built a new computer....

I fear the game is not optimized for certain hardware configurations. This is not an installation problem, or a windows problem. I did both before I built this new computer.