This error has the following cause and solution:
If you want a project to always use a specific version, and not receive checked-in changes made in other projects, you can share a specific version of the file using the Pin command in the History of File dialog box.
If you want to start modifying the file from an old version, you can roll back the file. The Rollback command only affects the current project; it performs an implicit separate operation. Both branching and rollbacks are available from the History of File dialog box.