Outlook 2010 Keep prompting for the username and password.??

Problem:

Outlook 2010 Keep prompting for the user name and password.??

Solution:
Step 1: 
Create a new Outlook Profile
For Microsoft Outlook 2010 and Outlook 2013
Start Outlook.
On the File tab, click Info, and then click Account Settings.
On the E-mail tab, click your email account.
In the Account Settings dialog box, under Selected e-mail account delivers new e-mail messages to the following location, you see the path and the file name for the .pst file that is associated with your email profile. For example, the path and the file name on Windows XP computers may resemble the following:
C:\Documents and Settings\user_name \Local Settings\Application Data\Microsoft\Outlook\Personal Folders(1).pst
On Windows 7 computers, the path and file may resemble the following:
C:\Users\User Profile\...\Microsoft\Outlook\User@contoso.com.PST
Note the path and the file name for the .pst file that is associated with your email profile.
For Microsoft Office Outlook 2007
Start Outlook.
On the Tools menu, click Account Settings.
On the E-mail tab, click your e-mail account.
In the Account settings dialog box, under Selected e-mail account delivers new e-mail messages to the following location, you will see the path and the file name for the .pst file that is associated with your e-mail profile. For example, the path and the file name may resemble the following:
C:\Documents and Settings\ user_name \Local Settings\Application Data\Microsoft\Outlook\Personal Folders(1).pst
Note the path and the file name for the .pst file that is associated with your e-mail profile.
For Microsoft Office Outlook 2003 and Outlook 2002
Start Outlook.
On the Tools menu, click Options.
On the Mail Setup tab, click Data Files.
Note the path and the file name for each .pst file that is associated with your e-mail profile. For example, the path and the file name may resemble the following:
C:\Documents and Settings\ user_name \Local Settings\Application Data\Microsoft\Outlook\Personal Folders(1).pst


Step 2: 
Configure the new profile to use the .pst file that was used by the damaged profile
After you create the new profile in Outlook, configure the new profile to use the .pst file that was used by the damaged profile. To do this, follow the steps for the version of Outlook that you are using.
For Microsoft Outlook 2010 and Outlook 2013
Start Outlook.
On the File tab, click Info, and then click Account Settings.
On the E-mail tab, click your email account.
Click Change Folder in the Account Settings dialog box under Selected e-mail account delivers new e-mail messages to the following location.
Click New Outlook Data File, click Office Outlook Personal Folders File, and then click OK.
Locate and then click the .pst file that was used by the damaged profile, and then click OK.
For Microsoft Office Outlook 2007
Start Outlook.
On the Tools menu, click Account Settings.
On the E-mail tab, click your e-mail account.
Click Change Folder under Selected e-mail account delivers new e-mail messages to the following location at the bottom of the Account Settings dialog box.
Click New Outlook Data File, click Office Outlook Personal Folders File, and then click OK.
Locate and then click the .pst file that was used by the damaged profile, and then click OK.


Step 3:
Start Outlook in safe mode
To start Outlook in safe mode, follow the steps for the version of Windows that you are using.
For Windows Vista/Win 7 / Win 8
Click Start, type outlook.exe /safe in the Start Search box, and then press ENTER.
Or
 Click Start, and then type Run.
In the Open box, type outlook.exe /safe, and then click OK.


Step 4:
Disable COM Add-ins:
For Microsoft Outlook 2010 and Outlook 2013
To disable COM add-ins, follow these steps:
On the File tab, click Options.
Click Trust Center, click Add-ins, click COM Add-ins in the Manage list, and then click Go.
In the COM Add-Ins dialog box, click to clear the check boxes for any COM add-ins that you want to disable.
After you disable the add-ins, click OK, and then restart Outlook.
For Microsoft Office Outlook 2007
To disable COM add-ins, follow these steps:
On the Tools menu in Outlook 2007, click Trust Center.
Click Add-ins, click COM Add-ins in the Manage list, and then click Go.
In the COM Add-Ins dialog box, click to clear the check boxes for any COM add-ins that you want to disable.
After you disable the add-ins, click OK, and then restart Outlook.

Step 5:
Back up your registry and remove the user account information from the "Protected Storage System Provider" sub key. Then, reenter your password options.
To do this, follow the steps for the version of Windows that you are using.
Back up the registry key
Click Start, and then click Run.
In the Open box, type regedit, and then click OK.
Locate and then click the following registry key:
HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider
On the File menu, click Export.
In the Save in box, select a location where you want to save the .reg file.
Type a file name in the File name box, and then click Save.
On the File menu, click Exit.