The short version: When generating a report from an RDLC, it throws a LocalProcessingException, with the message "An error occurred during local report processing." There is an InnerException of type ProcessingAbortedException, with the message "An error has occurred during report processing." There is one further InnerException, a ReportProcessingException, with a message that is the same as the name of my data set.
The background: I am converting a .rdl to a .rdlc. I copied my .rdlc into a .rdl, changed up data source stuff, and ended up seeing the above error chain. I removed all the expressions, but still got the same exception. So, I created a new .rdlc and recreated the functionality of the original .rdl (so, it is now its own source code, not just a modified copy of the .rdl). It returns the same error chain as the other version.
What would cause this, and what is the best way to handle it?