Engineering Mode

i have a problem with this AT Command.

why it does not work?
I using SC600T-EM

I recommend you use the serial tool to debug and try again (715.5 KB)

I tried using that tool. When I do send AT command nothing appears

1.Please confirm that the module is correctly installed
2.Check whether the serial port is occupied by another serial port tool

When the kit arrived I installed the drivers present in the key. QNavigator works but QCom no. Do you have any suggestions? Did I forget any steps?

now, I have managed to get QCOM working, but even here I cannot activate the engineering mode. Can you tell me the reason?