TFS build server - don't run test

Some tests will not run on your build servers because they haven't got connectivity etc.
You can prevent them running using a "TestCategory".
On the TFS build process tab
-> Automated tests
-> Test Source
-> Test Case Filter set to e.g. "TestCategory!=WebService"
Annotate your server with -
 [TestMethod]
        [TestCategory("WebService")]
        public void AckExistingMessage_AckSucceeds_MessageRemovedFromQueue()