steam authorization failed alteriw FIX

Earlier today and out of the blue, I received the following error message as soon as my MW2 alterIW session was about to start:

steam authorization failed 

well, First off, I was not even logging in to the official alterIW server, but to a dedicated server with some friends. After a little bit of digging, I found a solution that fixed the issue for me. Do not try to follow this is you cheated and got your butt banned, it will not help. nor you would deserve help in the first place  >:(

First you have to delete the following files ( move them somewhere else or rename them, whatever)

caches.xml and steam_api.dll from the game folder, and inside bootstrap folder delete caches.xml

now open the game, wait until you’re in the main menu, minimize and go do whatever you do when you’re not playing MW2 online, go out, and meet some real people! kidding, just keep it minimized for sometime, in my case around 10 mins was enough, The alterIW says 30 seconds, I tried that but the steam authorization failed message was still there.

Now run alterIW again it should work. In my case it did.


Although I’m not so clear why this append in the first place, I managed to get rid of it. if you are still getting it after following this guide you can try this method that one of my friends is using.

If you do have a backup of the game, then great, erase your copy and replace it by the old backup, it should work fine. If not, reapply the AlterIW modification to your installation.

If you have any questions, please ask, it may help us get to the bottom of this.
+1 if this helped you!