I visited both URLs, but I got "Page Not Found 404" error, and was redirected to the home page.
I suppose the problem is caused by trying to Redirect to another page using Response.Redirect while the RadCaptcha updates its image using Ajax requests. Please note that it is not possible to specify different URL so that the "Refresh Image" LinkButton will post back to another page.
Could you please open a new support ticket and send us a sample project that demonstrates the issue, so we can debug it locally?
All the best,
the Telerik team