When a user runs an activity such as Build that needs write access to the project's files, the activity locks the project to prevent other users from changing those files at the same time.

When a project is locked, other users can access any of the project's files that are in the shared area, but only in read-only mode.

Each user must check in changed or new files and to unlock the project when they have finished working on the project. However, the DPM administration user has access to all projects and can perform these tasks if necessary.