Creo Layout > References > Data Management > About a Locked Workspace
  
About a Locked Workspace
You lock a workspace to maintain the state in which the workspace was exported. Locking a workspace prevents any unintended changes to the workspace cache and helps to minimize the conflicts that may arise when the workspace is imported back. You can lock or unlock only one workspace at a time. For more information about locked workspaces, search the Data Management area of the Help Center.