Error: ... while Refresh is being deferred.

[Jim]

I am getting "ERROR: Cannot change or check the contents or Current position of the ICollectionView while Refresh is being deferred." in an error popup dialog box, when attempting to drag a state (as in NY, RI, VT) column to the grouping bar in a Silverlight RadGridView.

Controls are trial version Silverlight 4_2010_1_0515. Application is Silverlight 4.0 out of browser using RIA services for data.

Any idea where I should start looking for the problem?

Thanks,
- Jim Mead

[Vlad]

Hello Jim,

 Please try our latest official service pack instead and let us know if you still have such problems. 

Sincerely yours,
Vlad
the Telerik team

[Jim]

Thanks Vlad,

I resolved the problem this morning.  It was the result of multiple RadGridViews sharing the same RiaControls: DomainDataSource.

When I gave this RadGrid a copy of the DomainDataSource dedicated to that one RadGrid, the problem went away.

Having mentioned trying the latest patch -- The last time I tried a different install, I wound up with mixed versions references in the VS Toolbox, and in my project.  --  Made a mess, needed to uninstall one version and needed to start a clean project.

What is the correct of way of upgrading?

Thanks
- Jim Mead

[Maya]

Hello Jim,

You can find detailed information about upgrading of RadControls in our online documentation. 

Best wishes,
Maya
the Telerik team