Rules and Guidelines for MassUpdate
Use the following rules and guidelines when you run MassUpdate:
If the node running the Repository Service process has limited memory, disable repository agent caching before you run MassUpdate or restart the Repository Service after you run MassUpdate.
You can update reusable and non-reusable sessions.
You can update the value of any supported session or session config property whether or not it is overridden.
You cannot revert property values after you run MassUpdate.
You cannot update sessions that are checked out.
You cannot update sessions in frozen folders.