BleepingComputer.com: Disconnection To The Internet All Of A Sudden

I have been having problems with my internet. for some reason I will just not be able to connect to the internet with my computer but all the other computers in my house work flawlessly, so I know that the problem is to do something with my computer. This is about the fifth time this has happened, I won't be able to connect at all and then after about three days it will work fine again. I just bought Age of Conan (MMORPG) so I NEED to have good internet connection to play. I have de-fragged my hard drive and have done countless restarts of my computer and router/modem. I just don't know what to do any more. Any help would be greatly appreciated. Thanks.

Computer Specs:
Nvidia GeForce 8600 GT
Duel Core E2140 (rated at 2.75 ghz)
3GB RAM
Windows Vista Home Basic

How many "other" machines? With all them switched off does yours work? Do any of them have static IP addresses that could be conflicting with yours? Does your network use DHCP and is there enough IP addresses in the range to give out? Lots of questions not many answers, sorry. If it works sometimes but not others we need to figure out what is going on when it doesn't work and why.

I have 3 computers total (including my computer) and an xbox 360. I use DHCP connection and even with all the other computers off and my 360 off it still doesn't work. Hope that helped out a bit.

My initial guess is that you are turning on your machine first, which is getting an IP address assigned by the DHCP Server, sometime later your Xbox or other machine is getting switched on which may have an IP address manually set to the same IP address as your machine, this effectively kicks your machine off the network until your machine applies for a new ip address. If your machine goes on after the Xbox or other pc then the dhcp server gives your machine an ip address not already in use, that is why it only happens sometimes.

Click on Start button > Run > and Type command cmd > Press [enter] key

At DOS prompt type the command:
C:\>ipconfig /all

That should let you know about how long you IP lease period is set to. If it looks about 3 days then that may add weight to the explaination.

An option could be to take the details output from that and manually set the IP address, Subnet Mask, Default Gateway and DNS Servers for your machine but change the IP address of your machine to be something in the same range. i.e. if your current IP address is 192.168.0.2 change it to something like 192.168.0.22.

If you can get into your router settings with all the machines switched on your should be able to tell which machines have what IP addresses assigned to them, just pick an address that hasn't been used before.