I am asking this question because I had a lot of problems with getting the report data to work with my report and the other answers did not work for me.
Task: The data source of the report is outdated and needs to be refreshed.
Problem: Refreshing the data Set in the Report Data viewer will make visual studio crash.
This happened to me using Visual studio 2012.
I found the answer to this question after searching around a bit in the rdlc file.
You can open the rdlc file in a text editor like notepad++.
Search for: "SchemaPath", this will show you the link to your schema.
In my case the schema path was wrong and I had to change it so it could find the new schema. When this is changed to the right path, you can then refresh your dataset in the Visual Studio Report data view.
You can open the report data view with the key combination: CTRL+ALT+D.