The good news, it is easy to fix this issue. Open regedit program (Note, it is not recommended to use this tool if you are not a technician or system engineer).HKEY_LOCAL_MACHINE\Software\Clients\Mail\Microsoft Outlook
I highly recommend that you use the Microsoft Fix it tool, to automatically fix it for you.
Here's the link for detailed information.
Well, in this case this is not fully automatic. After you run the Microsoft Fix it, you need to manually repair your MS Office 2010 programs. Here's how to do it.
Click Start, click Control Panel, click Programs and Features, select Microsoft Office 2010 and then click Change button. Next, click Repair, and then click Continue. It will take 5-10 minutes to complete.