I found this great post. I think this is what's happening. Just want to share. Thanks again.

I had the same problem.  Seems like the SQL execution plan was corrupted for...

Thanks for the reply. Any idea how I can avoid this from happening again? It had happened more than once.

Thanks.

Is your user using a DB account or Windows account? Sounds like you're using Windows auth. Try DB account and see if it works. Definitely a security issue.