No M Key Error Message
The “No M Key” message shows on your pin pad screen & you are unable to complete transactions.
This message may also read “Pin Pad Has Lost Encryption Key.”
This may occur if the unit is connected to a power source before the pin pad being connected to the terminal. All parts & cords must be connected to each other prior to being connected to your power source (outlet). Physical damage to equipment may also cause this error.
Solution:
Unplug the terminal from the power source.
Ensure the pin pad is plugged into POS terminal.
Reconnect device to power source.
If you’re still having trouble, please Submit a Support Ticket.