OK people. I have been having this problem as I use Windows Live Email. I have a main account and three subaccounts. All were working fine until something at Verizon not only stopped my internet, but created email problems, The main account and one subaccount worked, but two subaccounts said the passwords were incorrect.
After two days of frustration on sub-account password changing, here is the snswer (with Verizon's Asian support):
1. Logon to: webmail.verizon.net
2. Click on "Forgot Your Password?"
3. On this screen put your subaccount name in the "Enter User ID" box (not your main name)
4. On this screen I answered my secret question (from the main account) or you could do the call thing.
5. On this screen enter your new password for the subaccount.
6. You should verify in your email software your password so it matches with that you just entered at Verizon.
It worked for me on both subaccounts!