Hi Matthew,
I and not quite sure which version of the Telerik.Web.UI assembly you use, but I can recall that we had a problem with items, which result size sum exceeded 10000. The problem turned out to be actually in jQuery (
http://bugs.jquery.com/ticket/7193) and we fixed it for Q3 2010 SP2. That is why, in case you are not using the latest version of the assembly, please test your page with it to see if the problem is already fixed. In case this tip does not help you, please open a new support ticket and send me a running test project, which I can use to debug the problem.
Best wishes,
Tsvetie
the Telerik team
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