Check the hardware IDs in the device manger:

http://dellwindowsreinstallationguide.com/downloading-drivers-checking-hardware-ids-and-downloading-and-installing-dell-system-drivers-in-the-correct-order/checking-hardware-ids-in-the-device-manager/

If the wireless card is not shown under network adapters press [Fn] and [F2] to turn on the wireless switch and let me know if theres any changes.

Thank you very much for your reply. I'll try this when I get home tonight and let you know how it goes.

Check your configuration on Dell's support site. If you have an Intel 1030 wireless card you can find the correct driver https://downloadcenter.intel.com/download/27042/Intel-PROSet-Wireless-Software-and-Drivers-for-Intel-Centrino-Wireless-N-1030?product=59481at, The correct driver is  WiFi_Win7_64_18.40.4. It worked on my Win7 64bit. On the same page are drivers for most operating systems.