I'm having a big problem with the serial communication..

I have a Romi Discovery 1250 machining center with Sinumerik 810D, and, i'm using Nclink to transmit the data...

i still can't comunicate the machine with the computer....

the cable config (as seen on the manual):

CNC db-25----------PC db-9
2---------------------2
3---------------------3
7---------------------5
4-5 jump 4-6 jump
6-8-20 jump 7-8 jump

Serial port config:
Badrate: 9600
Data bits: 7
Stop bits: 1
Parity: none
Flow: xon/off
Start at pc

I don't know what is wrong... Someone can help me?

Thanks in advance!