When trying to load new emails on my mail app it says "Cannot Get Mail The username or password is incorrect". It has been working fine since I got it 4 months ago until today. I tested my username and password on my mail account online to see if it had been hacked and it works just fine, so it is correct. I also tried re-entering my email address and password in the mail settings, but it still says they are incorrect. Can anyone help me, as this is very inconvenient?
eg: Are you trying this with Google? If so, they have changed things that if account gets checked too much remotely that it will lock account (except via web) and you have to go to their Captcha site to unlock.
Ive had the same problem, my hotmail stopped working on the 15th Nov. I tried every hint and tip I found online and the only one which worked was to delete the account and set it up via Microsoft Exhange under the "add account..." option. I just entered my hotmail details and used m.hotmail.com as the server.
Hope this works for you too.