When your TFS Lab test agents can’t start check the DNS
Lab Management has a lot of moving parts, especially if you are using SCVMM based environments. All the parts have to communicate if the system is work. One of the most common problem I have seen are due to DNS issues. A slowly propagating DNS can cause chaos as the test controller will not be able to resolve the name of the dynamically registered lab VMs. The best fix is to sort out your DNS issues, but that is not always possible (some things just take the time they take, especially on large WANs). ...