I have 1 user having this problem on her Outlook everyday ( microsoft security username and password request) pops up.
I've tried these so far, no luck.
1. Select File -> Account Settings -> Accounts Settings -> Then select the Exchange account that Outlook is prompting the login credentials for and click Change.
2. Click on More Settings.
3. Select the Security tab and check the box next to Always prompt for logon credentials.
1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then right-click the following registry subkey: (the subkey originally listed here was not present on my computer; this one worked for me: HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Security)
3. Point to New, and then click DWORD Value.
4. Type PromptForCredentials as the name of the new registry entry, and then press ENTER.
5. Double-click the PromptForCredentials registry entry, and then type one of the following values in the Value data dialog box:
1. Go to Control Panel ==> User Accounts ==> Manage your credentials
2. Under Generic Credentials you will see your Outlook Saved Password. My belief is the password saved in this area is invalid. Remove the saved password and log on to Outlook.
3. When I looked at User Accounts, Credentials, she had 6-8 ID's up under Generic Accounts all of them Outlook. I deleted all of them, which will force it to use the domain logon account. So far it appears to have worked.
In order to fix the random password popups with Outlook where BPOS was previously installed, navigate to this folder in Windows Explorer(the %userprofile% text will be replaced by Windows automatically with the correct path):
Then go into the subfolder that's named after the Outlook email address.
In that folder, rename or delete these two files:
If you're on Windows 7 and change your password on a regular basis follow these steps:
1. Click Start
2. Click Control Panel
3. View by: Small Icons
4. User Accounts
5. Manage your credentials
6. Delete everything in here.