When configuring a new lab environment for a client, I encountered the following error:
Environment message: Type=Error; Message=TF266044: One or more machines are not ready to run workflows. For more information, see the individual machine errors.;
Machine name: XXXXXX
Machine message: Type=Error; Message=Error occurred while configuring TFSBuildServiceHost with Lab configuration. ExceptionType:Microsoft.TeamFoundation.Build.Client.BuildServiceHostAlreadyExistsException. ExceptionMessage: A build service host already exists for computer XXXX.domain.net. Specify a different computer name and try again.
I found the solution in the following blog post (http://blogs.msdn.com/b/lab_management/archive/2010/02/09/additional-upgrade-script-for-fixing-build-agent-registration.aspx). Although our TFSenvironment wasn’t upgraded from the Beta 2, the fix still works if you encounter this error message.