Error queuing build: Http status 401: Unauthorized

Mar 17, 2009 at 12:55 PM
Edited Mar 17, 2009 at 1:21 PM
I have configured the buddy build web service and verified it from the browser (http://<servername>:8020/IntegrationService/BuildService.asmx). The methods are invoked properly.
However, when I queue a buddy build from a client machine, I get an error - "Error queuing build : The request failed with HTTP status 401: Unauthorized."
This is not the case when I try it from the server machine where the buddy build web service is installed (TFS, Build and web service are all on this server m/c.)

If I configure buddy build to Bypass the web service, the build is triggered fine even from a client machine. (My account has the build services permissions).

What might be causing this problem?
Searching on the net, I found something that could be related -
"When you use SOAP over HTTP and Visual C# .NET XML Web services on a computer that is running Microsoft Windows XP or Microsoft Windows Server 2003, you may intermittently receive an error message that is similar to the following: System.Net.WebException: The request failed with HTTP status 401: Unauthorized."
( &

Please help resolve this.


Mar 18, 2009 at 2:41 AM
Hi Salman,
The KB articles you referenced are specific to v1.1 of the .NET Framework. The web service uses v2.0. Also, which release of the tool are you using? There was a bug with the web service that was causing the 401.3 unauthorized errors but that was fixed in the last release of the tool on Jan 15 (v1.0.0.66).
Mar 18, 2009 at 11:23 AM
Hi Mohammad,
I had initially installed a previous version to try out the tool but at that time had not installed the web service. But before installing the web service, I uninstalled the previous version and installed v1.0.0.66 and got that error.
Mar 23, 2009 at 7:01 PM
Hi Salman,

Sorry for the late reply.
Are you still having this issue? Assuming you have the latest version of the VS add-in installed ( or, can you confirm whether you are able to queue a request successfully if you configure the website in IIS to use Anonymous Authentication instead of Windows Auth? Please let me know if that works. Also, can you confirm that the identity of the website's app pool is set to a user account that can be authenticated against TFS?