Hmmm, this did work the other day - I don't know if the folder permissions reset or something, but it's not working now. I've tried opening the permissions for every DEFCON-related file and folder I can find (including the entire steam folder) but nothing is working again :( Maybe I'm just ultra con...

Thank you!

My game is finally working! Steam still haven't gotten back to me

Cheers Xander - I appreciate your help!

Couldn't find the key - did a search, looked in the applicable folder but there is no authkey to be found. Have since been over to the Steam forums and it looks like a few people are currently having the same issue - hopefully Steam will have a resolution!

Help, anyone?

I assume this is the issue (http://introversion.co.uk/defcon/suppor ... blems.html) but that only gives a fix for Windows.

I'm not sure where to find those file locations you mentioned. I looked in the Defcon application folder and steam but couldn't find them. Apologies if I'm doing the wrong thing by posting this massive block of text; this is the error report: Process: DEFCON [2071] Path: /Users/USER/Library/Applicat...

I bought DEFCON as part of an indie bundle on the Steam sale a couple of days ago, it says I have an invalid key before booting me.

Is this a known error? Any advice? Would love to play the game!