Try this: Click on Tools, then Accounts, then your email account,
then Properties, then Servers. Enter your username and password
again, with any repeats needed for the password. If there is a
check mark in the box before Remember password, click on this
box to remove it. Click on Apply. Click on the box before
Remember password. Don't click on Apply; a quirk makes this
erase the password when done after you set Remember password.
Click OK, then Close.