We have tested this with a simple web forms application, RadSiteMap and RadMenu added on the Login page and domain different than the default, but we were not able to reproduce this problem.
Could you please provide us more details on the exact issue that you are currently experiencing? For example: the issue you are facing is with RadMenu or with RadSiteMap? Where exactly did you add the control? Are there any errors thrown on the page? Are there any missing resources? Are there any others Telerik RadControls for ASP.NET Ajax with the same problem?
Also can you please provide us with a screenshot of the page with the issue?
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