Arduino not detected

Hi All,

I have designed my own board using the ATmega32U4 and would like to bootload it with the Arduino boot loader from SparkFun found here. I have programed in the boot loader using my ATMEL-ICE though ATMEL studio 7. when I plug in the USB cable into my board it is detected an an unknown device as shown in the device manager below:

Strangely enough when I plug my ATMEL ICE into the board and read the fuse bits using ATMEL studio 7 the computer detects the board as an Arduino as show in the device manager below. once detected I can open arduino IDE and program the board without issue. However when i disconnect the ATMEL ICE the board is re-connected as an unknown device. Any ideas what i have done wrong?

Problem solved!

Turns out when i soldered the micro USB receptacle the ground pin was not soldered properly. This meant that when only the USB connector was used there was no common ground between the PCB and computer but when the ATMEL-ICE was connected it created a common ground allowing the board to be correctly identified.

I doubt someone else will have this issue but it doesn't hurt on the off chance this helps someone else.