Telerik doesn not have such version 4.1.60623.0, but System.Web
assembly does. Please be sure that you are watching the version of Telerik.Web.UI.dll as on this screenshot
Because this issue is unknown for us we will have to inspect your css. It is possible to have your own css that overrides the default combo styles. In order to do that we will need a link to your live page or you can send us a small sample replicating the issue.
the Telerik team
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