When you open any object in System Architect, such as a definition, the database record for that object is locked, to prevent other users from accessing the same record. If someone else tries to open the same definition, they receive a message that says “Definition X is in use by UserY”. When the user closes that object, the lock file is removed and others can access it. This protection makes shared encyclopedias possible.

However, there are scenarios, such as an improper Windows shutdown, when the lock fails to be removed, and an object remains in a locked state, even though no one is using it. Removing the lock file in this scenario is the main purpose of the Unlock Objects option. SAEM (System Architect Encyclopedia Manager) lets you manually remove a lock file from one or more objects.

Do not remove a lock file when another user has an object open. For example, suppose a colleague opened a diagram, but did not close it, even though they left for a three hour meeting, and you just need to edit that diagram. Although it can be done, with the proper rights, you should not unlock the diagram object. It is recommended that you ask him/her to close the diagram so you can open it.