Password Incorrect error iPhone 4
I updated my iPhone 4 with new IOS 5. I have a Gmail account which I use with Microsoft Exchange is giving me the following error. "Password Incorrect: Enter the password for the Exchange account." I removed my mail account and created it again. Verification process has done successfully. Anyway, when I go to check a mail, this error popup. I do not need to use it as a POP due to using Gmail calendar besides my Mac one. I am sure that the password I entered is correct. Case-sensitive is ok. I searched through the forums and found another person solved this by re-adding but it did not work for me. Is there anyone who knows how to solve this error?
I am thankful for your suggestions.