Telemecanique PC to PLC com problem

I have problem communicating with Telemecanique PLC using the serial port on my portable. Either with a Zelio, Twido or Micro communication is at best erratic, if possible at all.

I don't have any problem communicating through my com port with other brand PLCs.

Can someone help? My PC is an HP portable running XT professional (but had same problem with home edition) my Unitelway driver is version 1.7. For the Twido and Micro I use the TSX PCX 1031 cable.

Thanks.