Can't use serial monitor

Hello,

I am using the Esplora board for a project. When I connect the board to my pc (OS Windows 8.1), drivers for the esplora board and for the bootloader are installing. I can upload the code by pressing the reset button during the uploading. The uploading works properly. The issue is that just after the uploading of the code, the connection between my PC and the board is lost, so I can’t use the serial monitor… there is no ports available in tools->port. I select the correct board in tools->board type.

As you can see on the picture, drivers are correctly installed but the pc believed that the board is not connecting => error code 45,but the board is physically connected.

I try to reinstall manually the driver without success.
I try to install the old driver of esplora without success.
I try to unistall the IDE 1.6.10 and reinstall it without success.
I try to install the driver ch341ser.exe as I can see it in some topics, but without success.
I try 2 others USB cable without success.
I try another esplora board but I have the same behaviour.

Do you have any idea how I can solve this issue ?

Thank you

Valentin

Looks like you have to upload via COM6 and Serial Monitor will use COM4 after that?

Disclaimer: Not familiar with the Esplora (or Leonardo).