Problem uploading to board

Hi,

ive bought a few ‘Genuine’ Arduino undos online, only they’ve arrived and don’t look like official arduinos to me. when I try to upload to them the following message comes up:

Arduino: 1.8.8 (Mac OS X), Board: "Arduino/Genuino Uno"

Sketch uses 5320 bytes (16%) of program storage space. Maximum is 32256 bytes.
Global variables use 103 bytes (5%) of dynamic memory, leaving 1945 bytes for local variables. Maximum is 2048 bytes.
avrdude: ser_open(): can't open device "/dev/cu.usbmodem1461": No such file or directory
Problem uploading to board.  See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
Invalid library found in /Users/sean/Documents/Arduino/libraries/audio_samples: no headers files (.h) found in /Users/sean/Documents/Arduino/libraries/audio_samples
Invalid library found in /Users/sean/Documents/Arduino/libraries/examples: no headers files (.h) found in /Users/sean/Documents/Arduino/libraries/examples
Invalid library found in /Users/sean/Documents/Arduino/libraries/audio_samples: no headers files (.h) found in /Users/sean/Documents/Arduino/libraries/audio_samples
Invalid library found in /Users/sean/Documents/Arduino/libraries/examples: no headers files (.h) found in /Users/sean/Documents/Arduino/libraries/examples

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

could somebody please help me with this, is their a way to make it work or have I just been ripped off?

The boards also are not showing up when I select TOOLS> PORT… yet my genuine Arduino does.

can somebody please help?

Examine the black chip near the USB port, look for it's part number on the top of the chip. If 16u2, the official drivers that come with Arduino ought to work. If it's CH340G or CP2102, you may need to download drivers (these are clones with different USB-serial interface IC's - though once drivers are installed, unless you need to reprogram the 16u2 (which these boards don't have) they will work fine, and seem more resistant to damage from (electronic) abuse than the official ones). Note that the correct drivers to use for CH340G on MacOS seem to change with every version of MacOS because Apple keeps changing things.

As for whether they are real or genuine (assuming they have a 16u2 as serial adapter), if you post a photo of the board, we can tell you whether they're real, clones, or counterfeits. (A clone does not duplicate the markings and branding of a genuine board, while a counterfeit does).

There have been a few reports of genuine boards having made it out the door without the serial adapter firmware loaded. In these cases, the device is listed in device manager (or whatever the equivilent is on mac) as an Atmel DFU device - and the firmware can be written to it using FLIP, which may well be easier than beating a refund out of the seller; someone else did this recently, though I can't immediately find the thread)