After replacing an old Motor (with Endat encoder) with a new model the servo amplifier S601...620 shows error F04.

The Endat protocol has been changed by Heidenhain. The firmware used in older S601...620 does not support this protocol. Please use, depending on the serial number, the following firmware version:
Ser.No. < 220.000 : Firmware version 3.76
Ser.No. > 220.000 : latest or current firmware version