Hello everyone. I'm here to confirm a solution to this issue (if you purchased the game through steam).
Go to the Demigod.exe location on your computer, which you can search for, but should be at the location
C:/ProgramFiles/Steam/steamapps/common/demigod/bin/demigod.exe
Right click the demigod.exe, and under the compatibility tab, check "Run as Administrator"
You should now be able to run the game, by double clicking on Demigod.exe here, or through steam. Steam community will probably not function over the game, but you'll be able to play multiplayer, and Alt+Tab out to set up voice chats via steam, or whatever.
Cheers.
tldr: It's not a problem with your info, it's a problem with Windows not letting the game connect to the servers. Can be solved by process above.