I solved the problem by myself eventually because nobody here is helpful and nobody cares the things which we mention.
Here is the solution; you have to get a C3G System Software floppy disks which are belonging to the robot according to its number and this number has to be match with robot's serial number. After that with the communication cable from the computer, you have to connect it to the FDU serial port inside of the electrical cabinet (not outside of the cabinet named COMP) and it is placed inside of the cabinet up on the right corner. And then switch on the system and also turn on the computer and go to the Dos mode. Plug the diskette 1/3 of C3G System Software which is belonging to the robot with serial number. And go to the inside of the diskette in Dos mode and call the C3GBOOT and then it will connect directly to the cabinet with FDU and the downloading process is going to begin. Then you have to plug the next diskette according to the instructions on the teach pendant screen.
After downloading the system software it is going to ask set to the TIME on the teach pendant and enter the time there. And then it is going to start for the first time. Now you have to make a turn set first and then go CONF-ARM-CAL and then make it calibrated.
Now the robot is ready to have a program via PCINT.EXE program. I think you know the rest.

Please if you know something about the COMAU robots share the things here with everyone.
Best Regards,
Hasan S.
Electronics&Robotics Eng.