Ok, so I preordered Fallout New Vegas on Steam on the 18th, and I've tried to preload it before it was released, it said the steam servers were too busy to handle it and to try again in a few minutes, I gave up after trying multiple times. After it was released, I tried to install the game, and it gave me the exact same error message, I tried reinstalling steam twice, and it didn't fix the issue, I also tried changing my download region, I tried multiple places in the US, as well as in Europe, none of them helped, I got the exact same error message. This is the first game I've bought on steam to give me this issue. I also tried bypassing my router, and I am still experiencing the exact same issue. I also sent steam tech support a save of my msinfo32 file, and they told me to disable all my startup services because of a possible application conflict, I told them that didn't make any sense because its only Fallout New Vegas thats being effected, and that I can install any other game just fine. I've been trying for 7 days to get this game to work, please someone help me, I'm getting very frustrated with all of this, and I'm seriously regretting buying this game, and I hope that if this isn't resolved, that I can get a refund for this very defective product.

Anyone??

Send a support ticket to Steam. It's on their end it sounds like.

Already did, they just gave me useless directions, none of which worked...

Try this: https://support.steampowered.com/kb_article.php?ref=5483-YUFN-0521 or https://support.steampowered.com/kb_article.php?ref=7241-EYON-2343

damn, i have never had a problem with steam but this would drive to the madhouse, good luckman

I tried both of those.. Neither worked, None of that changed a thing...

Can anyone help me with this??

Check your firewall exceptions.

Its not that, I can install other games just fine, including Fallout 3 with no issues whatsoever, I also disabled my firewall, just incase, and that didn't change a thing.
I'm from the US, and here are my system specs:

Intel Q9650 @ 3.0 Ghz
ASUS Rampage Extreme Motherboard
4GB DDR3-1600 Stock speed and timing
Sapphire Radeon HD 4870X2 Stock core and RAM speed
Windows XP x64 with SP2 (most current)

What boggles my mind is that every single other game I have installs and runs fine, and there is no mention of 64 bit OSes not being supported, and no mention of Win XP x64 not being compatible...