Why can't I make a call?

Was the dialled number entered in international format? All calls made from the Iridium satellite system with a Iridium "8816" service must be in international format.

If the service is a Telstra "01471" service then the Telstra calling formats must be used. Dial all numbers the same as you would from a standard mobile except fixed calls must have the Area code (0X) included.

Check the signal strength indicator. If the signal is weak, ensure the antenna has a clear line-of-sight to the sky and there are no buildings, trees, or tall structures around.

Try to register manually.

Is RESTRICTED displayed? Check the Call Barring setting.

Has a new SIM card been inserted? Check that no new restrictions have been imposed.

Check to see if fixed dialling list is enabled. If so, calls can only be made to numbers or prefixes that are on the list.