This is what just finally worked for me, and it pertains to those using Norton Utilities.
I use Norton Utilities as my Anit-Vir, and I think that was causing my login problem.
Open Norton Utilities, go to the “PC Security” dropdown, and select Manage Firewall>Select the “Program Rules” tab> Find Guild Wars 2 in the program list, and set the access level to “Allow.” My Login worked immediately after I did that.
Good luck, and I hope this helps some of you.