Internet Sharing via ethernet not working

I recently discovered the internet sharing option on my mac and starting using it a lot. I connect to the internet via ethernet so I shared from ethernet and connected to the network on my phone (android) or ipod and it worked great. I stopped using it for a few weeks and when I went to use it again, it won't work anymore.
I don't think I'm doing anything different, but now even though it says it's turned on and looks the same, my phone and ipod can pick up the network but can't actually connect to it. They see the network, I click connect, and they just load for 2 minutes and then say "disconnected."
In the sharing settings page I have it set to share from ethernet to computers with airport. Maybe that means only other mac's can connect? Except that I've always shared to airport and my phone, ipod, and friends PCs could use it no problem. When I read online about how to do internet sharing the instructions were to click the "wi fi" box, but that's not an option for me, only ethernet, firewire, and airport are.
I have a 3ish year old mac running OS X snow leopard 10.6.8.
Any help would be greatly appreciated! I really miss being able to share internet.

Airport and wi-fi can be used interchangeably in this instance.

I'd start from scratch. When you create the name and password for the wireless choose something different from before to ensure your devices aren't trying to use old settings