if does not work try to make the following steps:
Cick Start > Control Panel > User Accounts > Credential Manager.
Note: If 'View by' is set to Category, click User Accounts first, and then click Credential Manager.
Select the Windows Credentials option. Locate the set of credentials that has either Outlook or Microsoft Office in the name and then expand the corresponding folder.
Then click Remove.
Repeat step 3 for any additional sets of credentials that have the word Outlook or Microsoft Office in the name.
Then Outlook will prompt for your password one more time and it should keep it