Q:
Password is invalid
A:
I haven’t seen any forum posts saying there is a problem leaving the login screen on. There is one involving mobile devices and the game, where is you use a mobile device to log into the forum it causes the game to forget your password.
If that’s not it you can try contacting support, or just turn the game off after you play it. ^^
Ty for the reply. I will just make a ticket and see what they can do if anything. I’ll just make sure to close the login screen.
ArenaNet Communications Manager
Jaybird, I just heard in a meeting today that a few of our Mac players are having password problems. Do you happen to be playing on the Mac platform? Just curious.
In any regard, an agent will get back to you soon and help get this resolved for you, but the suggestion from AP would definitely do the trick, too. 
Communications Manager
Guild & Fansite Relations; In-Game Events
ArenaNet
Interesting to note, if I sign in to my second account on the forums using my iPad, the password to my first account is “forgotten” by the game and forums, and thus I have to reset it. It does not happen on any other browser or device. I can sign in and out with no issue using my windows machine. It’s just when I throw this bloody iPad into the mix.
And all who stood by and did nothing, who are they to criticize the sacrifices of others?
Our blood has bought their lives.
I’m on windows platform Gaile. And it hasn’t happened since I closed login screen.
Interesting to note, if I sign in to my second account on the forums using my iPad, the password to my first account is “forgotten” by the game and forums, and thus I have to reset it. It does not happen on any other browser or device. I can sign in and out with no issue using my windows machine. It’s just when I throw this bloody iPad into the mix.
I have password problems with my new iPad with iOS 7.0.2 and logging into the forum. I have to use my old iPad with an old iOS. It’s something to do with Apple products and the newer iOS.