Email - IPad - Cell phone sign in issues

Guys, Recently I started to use my phone to log into my forum while I am in the field hunting. I always get the incorrect user name or password deal pop up even when i KNOW 100% the user name and password is correct.

Yesterday I had a couple members ask me whats up with this as they experience the same thing with their I pads.

Also have been getting a handful on complains in the past month that when a NEW user goes to sign up, they get a pop up that their email address is invalid and so they have to make a new email account with someone else.

Just curious as to what could be the cause of these issues?

Has anyone had this problem and if so, what was the issue fix?