In Team Foundation Server 2005, a build definition is defined by the presence of the build configuration folder under the directory called “TeamBuildTypes” at the root of the Team Project in source control.
To edit a build definition, you must edit these files in source control. A quick way to view the build configuration folder is to right click on the build definition in Team Explorer and select “Edit Build Definition...”. Note that when talking to a Team Foundation Server 2005 instance, this action is the same as selecting “View Build Configuration Folder”.
This will then open the Source Control explorer, allowing you to download the files, check them out and edit them.
A Team Foundation Server 2005 build definition consists of three files in version control.