@Joe, Thanks for the info; but I think that I found the issue. In previous version of the Events module, there was no requirement to input a location into an event. However, it appears as if this is required for the current version. The database for the previous version inserted a NULL into the Location columns on the Events and the EventsRecurMaster tables. When I updated these tables to a valid placeholder value...all worked fine. I am continuing with my testing.