Well I did, and the issue seemed to be intermittent. Here’s what it looked like for me: Here’s what I found out. You can read about the issue on Microsoft’s Help and Support at FIX: You may receive an InvalidCastException error in an ASP.NET-connected Web application (http://support.microsoft.c... Unfortunately, there’s no immediate download or fix. You have to call Microsoft Support to find out if the secret fix applies to your scenario. In my case...