TG582N

[#1]

I have replaced an older router with the TG582N wireless router.  I successfully connected my desktop by cable, and my laptop, and Ipad by WiFi.  I tried to connect my second desktop by WiFi but the PlusNet connection did not show up, however my neighbours Wifi was listed.  Can anyone help me with some advice?  The desktop is an older PC, running Vista, and has a Dell Wireless Adapter, model D1450U.  The system worked fine before the change and it is not a signal range problem.
Any help would be greatly appreciated.

[#2]

Is the WiFi button light green on the router
Have you made sure the SSID & Password are inputted correctly as they are CaSe SeNsItIvE
Have you also tried connecting using the WPS button

[#3]

Try updating the wireless drivers or shortening the wireless network name (SSID).

[#4]

As ejs said it is most likely a driver problem.
Unfortunately the info I could find is not helpful.
Microsoft® Windows Vista does not include native drivers for the Dell 1450 Wireless adapter and there will be no 1450 Wireless adapter drivers available from Dell that are compatible with the Windows Vista Operating System.
There will be no future support for the Dell 1450  Wireless adapter in Windows Vista.

So it looks like you may have to buy a new, Vista compatible, wireless adapter.
I have been using one of these, £4.59 incl post, with a Vista laptop without any problems: http://www.ebay.co.uk/itm/300Mbps-Wireless-Adapter-IEEE802-11b-g-n-WiFi-300M-Network-LAN-Card-Antenn...
This is from China/Hong Kong, but if you don't want to wait 2 or 3 weeks for delivery you can get the same thing from the UK here £6.79 : http://www.ebay.co.uk/itm/300Mbps-300M-802-11n-g-b-USB-Wireless-WIFI-LAN-Network-Card-Adapter-Antenn...
Derek

[#5]

Some thoughts:
- The Dell 1450 adapter is 802.11a/b/g only so doesn't support 802.11n.  Is your router set to 'N' only?
- Have you tried turning off the wireless security on the router (temporarily) to see if that makes a difference?
As others have posted, you may be better off just getting a newer adapter.

[#6]

If the 1450 wireless adapter was working on Vista with an older 11g router, then some kind of drivers must already be installed and more or less working in Vista.
I don't think it's possible to set the 582n to an "11n only" mode, such a mode doesn't really make much sense anyway, backwards compatibility is an integral part of the wireless protocol.
I'd try shortening the SSID (wireless network name) first.

[#7]

Sorry for the delay in replying.  As advised I bought a new wireless adaptor and this cured to problem/  Many thanks to all respondents.
Regards