no, that is an error while building the search index.
Please tell me more about your environment.
Did you install mojoPortal from a pre-compiled release of version 2.3.6.6 or did you deploy a build you made yourself from source code?
Is it a web farm or cluster?
.NET 4 or .NET 3.5? Full Trust or partial trust?
Are you forcing a specific culture?
any other points about your environment that you can think of that I should be aware of to help you troubleshoot?
I would clear the log then try out Event Calendar Pro and then check the log again, maybe try again on a new test page and put a new instance of it on a new page and see what happens.
Best,
Joe