it happens to me too sometimes
when u close w3 and open it again too fast
even if u close the gproxy
it takes some time to remove from memory or some shit, like for example, u play some game, u exit game, quit gproxy, u even wait like 5 sec, u click again on xpam launcher, gproxy gateway, and then u cant enter, u need to wait more before u click again on xpam launcher after u quit w3 and gproxy, like 10-15 sec to be sure