I found a bug report dealing with this issue:
http://lab.msdn.microsoft.com/ProductFeedback/viewFeedback.aspx?feedbackid=c89412dd-5d71-4c93-9a3d-704df84fbdee
There are a list of workarounds given. I tried the following and it worked for me:
Workaround Description:
Find the HKEY_CURRENT_USER\Software\Classes registry key and clear the default value
Workaround Steps:
Open registry editor
Go to HKEY_CURRENT_USER\Software\Classes
Double click the default value
Delete the value that's in there
Click OK