I have a desktop and laptop that I'm connecting to a Dlink DSL-G604T modem/Router on a secure network (WEP). I have managed to connect the desktop without any issues, however the laptop has no connection to the internet. There is a wireless connection to the router as I am able to see and edit the routers details in a web browser.
I have checked all details entered including user names, passwords etc. but this does not seem to be causing the issue.
In short, the wireless connection is there, I just am unable to surf the web from the laptop.

Any suggestions
Thanks

Try updating your WiFi driver. It should be availible on your PC manufacturer's website. Also, is the desktop connected via Ethernet or also WiFi?

What kind of notebook do you have? (Manufacturer, Model Number, etc.) I'll be able to provide additional info if updating the driver doesn't work.

The desktop is connected wirelessly, and is working fine. I have tried connecting the laptop (Centoris F503) both through an Ethernet connection and wirelessly. On both occasions I can connect to the modem/router, but am unable to connect to the internet. Drivers are all updated.

See if Internet Explorer is the problem. When you open it, if it says page cannot be displayed, it is probably configured incorrectly or IE simply can't access the Internet. Try resetting IE. Open IE, click Tools, in the bar on top, and click Internet Options. Go to the last tab, and click Reset. If this doesn't help, try updating your IE version to IE7. If this doesn't help, try to access the Internet via Firefox. If none of this helps, try this, connect to a different WiFi hotspot to see if it's your router that has a problem. If it is your router, reset your router and configure it again to remove anything that's causing it to work incorrectly. See if any of this helps.