Error 'HTTP could not register URL http://+:8000/SpanService' using WCF in ASP.Net

When I tryinh to host the wcf service in my local pc using windows service then following error is shown.

"HTTP could not register URL http://+:8000/SpanService/. Your process does not have access rights to this namespace (see http://go.microsoft.com/fwlink/?LinkId=70353 for details)."

how can I fix this error?