Device does not react when I start the Pc

[sandra.dj...@gmail.com]

Hello,

I have a Velmex stepping motor controller. And I'm writing a C++ program in Visual studio 2015 that sends messages to the device. When I turn on the PC and run my program the device doesn't react. So then I open tera term and send a command to the device, the device reacts to the command and then if run my C++ program the device will react. But if a turn off the pc or restart it and try again the command, the device doesn't react until I open a connection using tera term send a message, disconnect and then run my program. Do have any idea why is that ?

thanks