Some AMU activities require the user to have exclusive control of the AMU system, so no other user can inadvertently perform conflicting critical tasks at the same time. Other users are still allowed to do non-critical tasks and activities, however.
If you have taken exclusive control, no other user can take exclusive control until you relinquish it, so it is important to remember to relinquish exclusive control when you are through with it.
To take or relinquish exclusive control of the AMU system, use the Actions menu or click the exclusive control indicator on the right side of the menu bar.