So I had bought the hardcopy of New Vegas when it first came out and played it, but recently I reinstalled it and the DLC straight off my steam account since the disc was in storage. I was playing it at home where I had internet and now moved to a place that doesn't have internet. When I go to start New Vegas a window from Steam pops up telling me it can't find an internet connection so I tell it to start in offline mode. But then another window pops up:

STEAM - ERROR
Could not connect to Steam Network.
This could be due to a problem with your internet connection, or with the Steam network.

I press ok and the game won't start.

So am I now S.O.L. in playing New Vegas? I played New Vegas before without an internet connection when I first bought the game. So why the change?

Its because before you play in offline mode you need to briefly play connected online. Its part of the "validation" process which I find absolutely stupid. I too have a hard copy of NV but its never even asked for the disk because it DLed the game off of Steam anyway.

If you have a smart phone you can tether the phone to the computer just so you can login to Steam then log-off into offline mode. Its stupid but it works.