WiFi - No Connections

You might try uninstalling the wireless NIC via device manager and then let the system find/install it again upon restart.

Roderunner thanks for another possible scenario but manually inputting IP addresses didn't work.

The problem I'm having is 'no connections' - no wifi networks detected not that I cannot connect to a network.
Actions taken already :
1) tried new drivers from Dell.
2) removed everything wireless in program & features, trying another install of the dell drivers.
3) installed a Belkin usb wifi adapter - still no connections visible
4) I can connect to my router & see my neighbors router with my smart phone.
5) The only difference I can see in device manager is that 'Microsoft Virtual WiFi Miniport is no longer under the 'Network Adapter' folder

I've hit a brick wall now - can only hope a re-install of windows works

Do you see the entry in the device manager for your wireless NIC? Right click on it and select uninstall then reboot.

Hi Username.. I've tried this many times just uninstalling & also deleting the driver software, just tried once more hoping it would resolve the issue. I'm afraid it didn't , Win 7 saw the new hardware on re-boot & installed the Dell 1397 driver.

Under the Network connections the dell wireless connection is still shown as disabled but in device manager it's 'enabled'..

I cannot 'enable' wireless connection from the sharing center.

sorry - I did not see where that had been mentioned as having been tried.
If you are willing - before re-installing the OS - try this:
Uninstall the Dell drivers
Restart the computer
Uninstall that NIC via device manager
Restart the computer
Watch to see if it finds a copy of the Dell drivers... hopefully it will just use generic drivers from W7.

When you installed the Belkin USB WiFi adapter - did it show as disabled too?
edit: I see where you already said that the USB showed as enabled but found no APs.
:::scratches head:::

Have you got a LAN cable plugged in?
Do these wireless NICs have a feature like:
Disable Upon Wired Connect

Sorry - also have tried this, when i removed all the dell software drivers & un-install the Nic card, on reboot win 7 finds a basic dell driver, doesn't seem to find a generic one.

Niether this basic one or the updated ones work, but I don't think it's a driver issue because I've also installed a Belkin usb adapter. This also fails the find any wireless connections although in the network connections its shown a enabled.

I've also checked that network discovery is turned on.

Hmmm, let us know how it goes after a re-install of the OS :-(

Clean Install with a Upgrade Windows 7 Version

or

Clean Install Windows 7

Thanks Username for your input - I think it will be a re-install but will not be for a few days yet I want to make sure I've everything I need as a backup on another disc just in case I have to go for a clean install.

The laptop was supplied with vista & upgraded to Win 7 with a dell upgrade disc. So not sure if it will go as I hope.