I tried to subscribe to workitemchanged events via mail, and this worked fine. Now I wanted to subscribe my self-made webservice.

So I created the webservice and put it on my C-drive. With the IIS manager I created a new Website beneath the "SharePoint Central Administrator"-website. I made sure the path was correct and the Directory Security was set to "Integrated Windows authentication".

When I test the webservice via Internet Explorer by typing in "http://computername:17012/websubname/MyService.asmx" everything works fine. However, when I subscribe this webserver to the tfs event service and the service wants to call the Notify method of my webservice, I see an error in the Application event log saying "URL authorization failed for the request". (I see in this logging the service was called correctly, and the username taken was tfsservice.)

Does anybody have any idea why this error occurs? What's the security trick to avoid this error..?