Check to see if you have the M1XRFTW or the M1XRFTW”M” version of ELK Two-way Wireless Receiver. Firmware 1.2.64 will only work for the M1XRFTW”M” version. If you have the M1XRFTW”M” is it connected to the M1DBHR Hub Retro Fit? If so remove from the branch on the M1DBHR and temporarily connect directly to the M1 Main board and try the update again.