806 syringe pump

Thank you for your answer, i already tried that and other settings such as  programmable baud or enable syringe.

i believe it is something on board like IC Programed Eprom Assy VK8000 or mainboard itself.

The baud rate should be set to 9600.

On the 8000, press PRINT. 

Select #5 "Set Baud Rate".

Set the baud rate to 9600.

Below is a link to the user manual describing this in more detail:

https://www.agilent.com/cs/library/usermanuals/Public/Agilent_8000_Op_Man.pdf

If the baud rate is set to 9600 on the 8000 and it is still displaying this message, I would try another null modem cable and check all of the cable connections.