Thank you for getting back to us. It seems that as Alex suggested the issue lies somewhere in the IIS server configuration. You need to check that all authorization rights are properly set. You can find this article
Also, you can try adding a sample file in the virtual directory and accessing it thought a browser. If there is an 'access denied' exception, in the browser you should be able to get more details of the error thus pointing you to the cause of the issue.
Unfortunately since we cannot reproduce the same exception in our environment, we cannot be sure what is the cause and this is why any details that you have about the exception might help us narrow down the cause and advice you what to look for.
the Telerik team
Thank you for being the most amazing .NET community! Your unfailing support is what helps us charge forward!
We'd appreciate your vote for Telerik in this year's DevProConnections Awards. We are competing in mind-blowing 20 categories and every vote counts! VOTE for Telerik NOW >>