Alright, so I figured it out. After uninstalling the game I found that there was still a Factorio folder lurking in my Program Files. I deleted that and reinstalled and it now seems to work like a champ. Thank you for the responses.

I have deleted and reinstalled the game and am still unable to play. I still receive the same error message. Any suggestions? I enjoyed the demo, paid for the game, and am very excited to play it.

I am currently running Windows 10. I deleted the demo before I downloaded the full version. Maybe I'll just delete everything and reinstall to be sure.

I downloaded and played through the Demo without any problem. I then paid for, downloaded, and installed the full alpha version. The game loads properly, but when I go to start a new campaign on any map beyond the 3 demo maps I am greeted with the following message:

"Unknown entity gate (Maybe you ...