To check the status of any MFP port that might be used for connecting MFP devices, do the following:
The Selected port pane displays the following information about the port: port type (parallel or USB), name of device connected to the port at the moment and port busy status. The latter status can be reported as "Port is unused" or as description of the operation being performed over the port. Possible formats of such description might look like "Application1 is printing" or "Application2 is scanning". Here Application1 or Application2 are names of applications using the port.
If a port is occupied by printing or scanning operation initiated by some application, the port becomes inaccessible for other "consumers". In case of abnormal termination of the current port's owner, the port remains busy and cannot be claimed further. To relinquish the port, you can press the Release port button. Please, avoid releasing the port while normal operation is going on. This results in immediate I/O error and the current job is terminated.
See also:
Ports configuration