File locking occurs on many types of network storage systems including ProMAX Platform servers and cannot be disabled.
File locking works by tracking each file that network users access, and when a previously unused file is opened, it assigns a temporary write-lock to the user who opens that file first. While that user is accessing the file, they are the only one that can write (and save changes) to that file and its associated folder path. Other users may access that file, however they will be granted read only access. If the primary user closes access to that file, the next user who opens the file is granted the write lock. While only one user can write to the file at any one time, any number of users can read from the same file simultaneously.
In most Post-Production environments, this does not affect users as each user is typically writing to a single file, their NLE or graphics project file.
For example, in an environment with 10 premiere users working on individual projects, all sharing the same batch of raw media, file locking would be applied like this:
One aspect of File Locking that can cause disruption if not properly understood is the locking of file paths. When a file is write-locked open, some environments (OSX/MacOS in particular) will lock open the entire file path of a file to protect it from being moved/deleted by another use while it's in use.
This means if a user opens the file "/Project-Alpha/NLE_files/CUT A/My_premiere_project.prj", that entire folder path will be protected against anyone else changing it.
As an example, this can result in confusion if a second user is tasked with changing the name of "Project-Alpha" to "Project-Alpha 1". Because there is a file in use by the first user in the "Project-Alpha" folder path, that entire path is protected from change until the first user releases the file. Until then, the "Project-Alpha" folder cannot be renamed, deleted, or moved as it would break the pathing to the file in use.
If you or your users are reporting that they cannot save a file, or edit/move/delete a folder on a Platform Space where they have full read and write access, they are likely being prevented from doing so by files and/or folder paths being locked open by other users.
Some programs react differently when trying to write to a file that is write-locked by another user. Here are some common behaviors that may indicate file locking is in play: