Hi kotu k,
We will highly appreciate it if you address the questions we have put forward in your previous ticket: "How to use the ComboBox, TextBox and Label with in the GridViewCell?" The answers to our questions will help us address your needs better, otherwise you may not get a response from us.
As to your question, RadComboBox does not support horizontal scrollbar, but you can always make the dropdown larger.
the Telerik team
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