two UNO's but only one will connect

I just got two new UNO boards from Adafruit Industries and one will connect to a Windows 10 PC and load a sketch just fine.
The other board will not show up in the ports in Arduino 1.6.12, but you can hear the computer "connect sound" when plugging in the USB.
Cant figure out, is it a bad board or do I need to do something for new board to connect.
Crazy thing is, every China made board i have, will connect fine.
Anyone got any ideals

What does the non-working one show in device manager?

It show up Just like the other
https://drive.google.com/open?id=0B0ll33r-IXcOOVdfT1FXUWhQdFk
Link to picture

Adafruit missed flashing the USB-to-serial firmware on the ATmega16U2. You are seeing the device running the DFU bootloader, which is the default factory boot loader on that ATmega16U2. You have 2 choices.

  1. Go ahead and flash the firmware yourself using a DFU program. The firmware is in one of the subdirectories of the Arduino installation. (a subdirectory called firmwares). Or flash it using the ICSP header close to the USB port, using the working Arduino as an ISP programmer. The example ArduinoISP sketch and a few wires is what you would use to do that. You can find tutorials and info online for either method.

or

  1. Post your screen shot and trouble description on the Adafruit website forum, and Adafruit will offer to send you a replacement.

Ok got it flashed, but when "upload" the sketch I get this error?

Arduino: 1.6.12 (Windows 10), Board: "Arduino/Genuino Uno"

Sketch uses 3,282 bytes (10%) of program storage space. Maximum is 32,256 bytes.
Global variables use 517 bytes (25%) of dynamic memory, leaving 1,531 bytes for local variables. Maximum is 2,048 bytes.
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0xe5
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xe5
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

They could have missed flashing the boot loader on the ATmega328P as well. Does the L LED blink when you tap the reset button on the bad Arduino, just like it does on the good Arduino?

No it does not blink

They missed flashing the boot loader on the ATmega328P. They probably made the board and then it missed the part where they upload the firmware to the ATmega16U2 and the bootloader to the ATmega328P. You have 2 choices.

  1. Go ahead and burn the bootloader yourself using the working Uno as an ISP programmer. The example ArduinoISP sketch and a few wires is what you would use to do that. You can find tutorials and info online for burning the bootloader. Once you have the wires connected between the programmer Arduino that is loaded with the ArduinoISP sketch, and the target Arduino that needs the bootloader, you would go on the menu to Tools, Burn Bootloader. On the Tools, Programmer menu you would select "Arduino as ISP". This is good stuff to learn. If these are your first 2 Arduinos, you are better prepared than most people who have just one Arduino and can't use one as a programmer to fix the other.

or

  1. Post your trouble description on the Adafruit website forum, include information about how the L LED does not flash when you reset the board and you think the bootloader was not flashed at the factory, and Adafruit will probably offer to send you a replacement.

or I just thought of a third:

  1. Buy an ATmega328P that has the Uno bootloader already burned to it, and switch out the processors. Save the old processor as a spare and to use as a "stand alone" processor in breadboard experiments. You need to be careful when prying out of or inserting into the socket to keep from bending/mangling the pins.