I kept running into a previlages connection problem last night with Punkbuster in BF2 on a vista OS.  Below is how to resolve the punkbuster issue in Vista.

 
Battlefield 2
We ran Battlefield 2 in both its native un-patched state and with the latest 1.3 patch, and both of them seemed to work just fine. There's one significant gotcha that crept up several times in our testing: Punkbuster. The Punkbuster anti-cheating code is a common part of many online games (particularly shooters), and it works by scanning game files to make sure they're not compromised. Most Battlefield 2 servers have Punkbuster enabled, and when we joined one, we got promptly kicked out of the game with a message saying Punkbuster failed due to "inadequate O/S privelages."

The solution is simple enough: right-click the BF2 icon, choose Properties, and then in the Compatibility tab check the box that says "Run this program as an administrator." After doing this, we encountered no problems joining any server.

Just don't use Vista. Problem solved.

Yep. I just switched back to XP two days ago. Sunday evening, I rebooted, and Vista seemed to think it would be funny if it refused to acknowledge that I had any user accounts. Repairing the install didn't do sh!t, so I went back to XP. I guess that's better, cuz I get to use blackbox again.

I actually am contimplating going back to xp, but vista hasn't caused me any significant problems....yet....emphasis on the word significant.  But I just finished re-installing all my games and proggies, so right now it would be more of a PIA to go back.

Same situation for me.  Installing everything on XP is a PIA.

On a related note involving punkbuster:

From my clan site which was found on another clan site:

Punkbuster, as you probably know, is the anti cheating software which comes bundled with 2142 and is required to play on all ranked servers and most public servers. Punkbuster scans your hard-drive for problems every 20 seconds. As you may have guessed, this causes a lot of lag.
What we are going to do in this fix is to increase the amount of time in between punkbuster checks to 500 seconds (the maximum amount so don't try anything higher lol). By the way, in case you were worried, this is 100% safe with punkbuster, and will NOT cause any problems with Punkbuster thinking you are a cheater. Punkbuster even recommends this fix on their website.

To do this you need to:
Join any 2142 online server which is running punkbuster, preferably a ranked one.
Once you are in, and respawned somewhere, press the `~(Tilda) key or you can just press end key.
A large white box should drop down with a load of text in it. Type pb_sleep 500 and hit the enter key.
Once you have done this, make sure the box is still up and type pb_writecfg to save your settings.

And for proof that this isn't some secret hacker's thing go here and scroll down to My computer locks up or "chugs" sometimes while I'm playing with PunkBuster Enabled, what can cause this? : http://www.punkbuster.com/index.php?page=faq-bf2142.php

A few of my clan members have tried it an it works. It helps to get rid of some of the lag within this game (and theoretically ANY game that uses PB).

or a brain? lol