Network security problem >.<?

Every single time I secure my wireless network the internet ALWAYS stops working it wont recieve any outside information, it wont display any web pages, I had to make it unsecured again to post this question, I used the router's settings page, I enabled the WEP key setting to mandatory and I enabled a mac address filter so only my computer would be accepted into the network... does anyone know how to fix this annoying problem...

Network security problem %26gt;.%26lt;?virus

Start by deleting the mac filter until your get the encryption settings going. I wouldn't use WEP as it's so easy to crack but before switching to WPA I would double check the SSID on your computer access card (Netgear is not the same as netgear). If your sure the SSID is good then double check the WEP key and make sure one device isn't using a passphrase to hex while the other is not. If this seems ok then I'd look at the firewall on the router to make sure the wireless side isn't locking you out. You'd have to give hardware specs for anyone to help with that.

Network security problem %26gt;.%26lt;?anti virus

after you make the settings on your router, try rebooting the modem, router and the computer and then connecting.
We would need to know what your network consists of. Desktop, wireless router and a laptop? If so, which one will not access the internet. Does your laptop ask you for your encryption key? Try WPA security if both of your devices support it. It is better than WEP.