Additional Features
Additional Features
This section describes other tasks you can perform, if required, on the MBU and the
Aastra 420d Handsets.
Resetting the MBU
In order for handsets to register with the MBU you must press the RESET button on the rear of the MBU. Each time you reset the MBU, the handsets must
Note: When you reset the MBU, the MBU waits until active calls have been completed on the handsets before starting the reset process. If a registered handset is off during an MBU reset, it reconnects when turned on as long as the MBU was not factory defaulted.
To reset the MBU:
• Press and release the RESET button on the rear of the MBU (do not hold it down)
On the front of the MBU, POWER lights steadily during a reset and
Note: Check to be sure all handsets are registered (or reconnected) properly with the MBU after the reset is complete.
Manually Registering/De-registering a Handset
Handsets will usually register without any action on your part if they are close to the MBU 400 after a reset. If required, you can manually register and deregister a handset. Make sure your handset is within range of the MBU.
To register or deregister the handset do the following.
1.In Idle mode, press OK z to display the Main Menu.
2.Select Settings 
and press OK z.
3.Select System settings, and press OK z.
4.Select Handset settings, and press OK z.
5.Select Register handset or Deregister handset and press the Yes softkey at the prompt.
If registering, the handset prompts to be placed in its charger cradle so auto- registration can occur.
Listing all Registered Handsets
To view a list of all registered handset do the following.
1.In Idle mode, press OK z to display the Main Menu.
2.Select Settings 
and press OK z.
3.Select System settings, and press OK z.
4.Select Handset settings, and press OK z.
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