As I have had problems with the VS2005 data source mechanism before (data source crash I), I have some experience in troubleshooting data sources. I stared out checking for invalid, zombie data sources in the \My Project\DataSources\ folder (VB.NET), and removed an old, unused data source. This did not solve the problem, but I prefer to diagnose a clean solution.
When I made the new business entity object that I was adding as the new binding source, I also refactored some of the other entity objects to remove some obsolete properties and changed some property names to reflect gained knowledge about the domain.
I found out that VS2005 is not fond of such changes in the assemblies used as object binding sources. It is however, quite easy to make the data sources reflect the changes:
- Select the project in the solution explorer
- Click the 'Show all files' button
- Navigate to 'My Project' and expand it
- Navigate to the 'DataSource' child node and expand it
- Select each of the data sources in turn
- Right-click the data source and select 'Refresh'
After refreshing the data source definition cache as described, VS2005 no longer performs harakiri in response to refactoring objects used as data sources.