If the option Drives->Remap->Timed is checked, a timer is used to check the mapped drives at a user set interval. The drives list is updated automatically if it is not current. Use of this option will cause automatic removal or addition, without any action by the user, of any remote or removable drive that has its status changed outside of the program.
A set interval dialog window only appears when the option is changed to enabled.
This option setting is also available on page 2_2 of the Settings Notebook.