QCOM not able to send AT commands to EG912U-GL on UMTS&LTE evaluation board

[Molleby]

EG912U adapter board is plugged in
Power comes from a normal 5v 2A supply to the USB power port
Power switch is in the ON position
USB-to-RS232 is connected from the eval board to my PC
All drivers have been installed
SIM card is inserted

“Power” LED is contant red
“Status” LED is constant green
“NET_STA” LED is blinking blue

I can access the board via the proper port in QCOM, but when I enter an AT command, nothing happens. Nothing at all.

[Bean.Wang-Q]

Make sure the “Send With Enter” be selected.
Please show the device manager and the QCOM.

[herbert.pan-Q]

Please check the ports in the device manager of your PC. Also, I have sent you the USB driver. Please insert the USB into your PC and try again.

[Molleby]

Installed the driver that was sent. Restarted everything. Used “Send With Enter”. Still nothing:

[Molleby]

Also, how the cable adapter appears in my device manager:

OS is Windows 11 Business, version 24H2

[Bean.Wang-Q]

If you are using the “COM Main”

It should be working. But if it do not work, maybe the Prolific PL2303GT USB Serial didn’t adopt the correct driver. Quectel do not have special driver for it. You can try right click the COM10 and update and choose the correct driver.
Herbert might provide you the USB driver, and it is not for the RS232 COM port. It should match with the microUSB port.

[Molleby]

Solved.

Somehow I missed the part in the documentation that defines the functionality of switch S901. It was set to BT/Wifi mode. Flipped it to UMTS&LTE mode and now QCOM works