When I first got GTA4, I absolutely could NOT get online. No random matches (ranked or player) would connect and I only got into one or two matches that I was invited to. It pissed me off to no end because I was really looking forward to the multiplayer.

After a day or two of no online play, I decided to do a little tinkering with my router. I upgraded the firmware, but that didn't do much (well, it DID give me access to my router settings, which I was constantly locked out of). I forwarded the ports that Xbox Live required, but nothing got better. After a few hours of trying to improve the situation, I had nothing to show for it.

Until I found a simple checkbox that made EVERYTHING better.

Now, I'm not sure if this will work for everybody, but it's worked for me and BunnyRabbit2, so I'm going to post it here and see if it works for anybody else.

NOTE: I play GTA4 on the 360, as does BunnyRabbit2, so I'm not sure how well this will work for PS3 owners. I think it will fix things for anybody having problems, but I'm not 100% sure. Also, this is only something you can do if your system is connected through a router, but I think the router may be the issue anyway. I'm willing to bet most people who have their systems connected directly to their modem aren't having many problems with playing online.

I also want to note that I'm going by what I had to do on MY router (which is a D-Link WBR-1310), so it may not match up perfectly for yours. If you have instructions (or can Google for some kind of help) for your particular router, that may help you find what you need.

HOW TO (MAYBE) GET GRAND THEFT AUTO IV WORKING ONLINE:

Step 1: Access your router settings

I'm pretty sure this is the same for all routers. Open up your favorite web browser and type in your router's IP address. Mine was 192.168.0.1 and I assume that's the default for most routers. It will probably give you a login screen, which will ask for a username and password. My router had the default username and password printed under the router itself (along with the router's IP address), so that would be a good place to look if you don't know what to enter.

The default for my router was "Admin" for both spaces. If you can't get in with the defaults, you may need to reset it by pressing a button somewhere on the router.

Step 2: Find your console's IP address

To do this, I had to have my 360 running, so make sure your console is powered on before looking for this. You may have to exit the router settings and renter them if your console isn't already on.

Somewhere in the router settings, you should find a list of all the clients connected to your router. For my router, I selected the SETUP tab and then NETWORK SETTINGS on the sidebar. Again, this may be different for you.

Once you find it, you should see a list of IP addresses for each of your devices (Dynamic DHCP Client List in my settings), which I believe is usually 192.168.0.10x for each one (my computer is 192.168.0.101, my Wii is 192.168.0.106, etc). The system may or may not have it's correct name next to the IP address, so you may have to use the process of elimination on this one. :P

My 360 was listed as unknown.

Step 3: Enable DMZ Host

Once you have your system's IP address (copy it or write it down), you need to find the DMZ Host option. Now, I'm not sure if this is available on every router. I'm not exactly an expert when it comes to routers, so I don't know if this is a standard feature. It was available to me and BunnyRabbit2, so I know I'm not the only one, at least.

To find this on my router, I clicked the ADVANCED tab and then FIREWALL SETTINGS from the sidebar.

You should find an option called DMZ Host. Here's the description it gave me in my settings:

The DMZ (Demilitarized Zone) option provides you with an option to set a single computer on your network outside of the router. If you have a computer that cannot run Internet applications successfully from behind the router, then you can place the computer into the DMZ for unrestricted Internet access.

Note: Putting a computer in the DMZ may expose that computer to a variety of security risks. Use of this option is only recommended as a last resort.

Now, I know it says that you expose your computer to security risks, but I don't know what that means for your console. I don't know how at risk your console is by enabling this mode, but I don't think there's much to be worried about. I haven't had any issues yet, and I don't think I will.

Either way, Enable this option at your own risk!

To enable the option, I simply had to paste my 360's IP address into the DMZ IP Address space and check the Enable DMZ Host checkbox. Save the changes, and.......

GET ONLINE!

Once again, I'm not sure this will work for everybody, but I've been able to connect to every match flawlessly since I did this.

Both 360 and PS3 owners: Please try this method if you are having issues and comment with your results. I'd like to confirm that this is actually a working fix for both systems. I know it'll be hard to resist the charms of killing hookers with 16 friends, but please take the time to comment whether it works for you or not.