Thank you for contacting us.
This is a known issue and it is already resolved. If you upgrade to the latest version it will not occur. Workaround for the version that you are using is available in the item's description
Please note that for columns where the underlying data cannot be sorted out of the box (like image columns) you should provide a custom type converter
or disable the sorting.
I hope this information helps. Should you have any other questions, I will be glad to assist you.
Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Feedback Portal
and vote to affect the priority of the items