When I press the left button, the LED will not turn on. I've tried replacing the LED, but yet, nothing happens.
Have no idea what 2.3 is.
Do you have the flat side of the LED going to GND ?
Looks like you might have the right switch interfering with the LED cct.
Let’s see the schematic.
Use diagonal corners with those switches.
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larryd:
Have no idea what 2.3 is.Do you have the flat side of the LED going to GND ?
Yes, I do.Looks like you might have the right switch interfering with the LED cct.
Let’s see the schematic.
Use diagonal corners with those switches.
Which diagonal corners do I want to use? Their diagram shows it the way I have it configured.
“ Which diagonal corners do I want to use? Their diagram shows it the way I have it configured. ”
It doesn’t matter, just use opposite corners.
Is the ‘right switch’ interfering in the LED wiring ?
Attach your sketch so we can see the complete code.
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Attach your sketch between code tags
[code]Paste your sketch here[/code]
Hi,
Is the yellow jumper connected to gnd on the controller, hard to see in the picture.
Can you please post your code?
Thanks.. Tom.... 
Can you post a link to the tutorial you are using?
If you take the link out of D5 and connect it to +5V does the LED light?
If you put it back and write a "1" to D5 does the LED light?
You appear to have the 220 Ohm resistor and white wire connected to the ground terminal of the right hand button. 
Paul__B:
You appear to have the 220 Ohm resistor and white wire connected to the ground terminal of the right hand button.
Doh! Thank you. That fixed it!
This was a hint that went way over your head from post #1
“Looks like you might have the right switch interfering with the LED cct.“
You must read . . . . .
Stronger hint required, wot? 
Stronger hint than: “ the right switch interfering with the LED cct”
Hmm, OP better take up fishing.