Example sketches not working.

Hi, I'll start off by saying I'm a complete beginner with Arduino and coding. My problem is, I'm trying to use the example sketches and it says they've uploaded but nothing happens after that. What I mean by nothing is I'm trying to make an LED blink but the LED doesn't even light up. The L LED was flashing on and off but is now just constantly on. All software and drivers have been installed etc. The TX and RX LED's flash when something is uploaded but like I previously said, nothing happens after that.

Any help would be appreciated, thanks.

P.S If I need to upload any information, please guide me in what I should be posting as I have no idea!

Thanks again.

Are you using the standard Blink sketch unmodified?
Which Arduino board are you using?