"Windows cannot connect to " router

[Dalinth]

Hello,
I recently upgraded security on my wireless D-Link router from WEP to WPA/WPA2 (the wireless network settings didn't say which). However, when I then tried to connect with my Windows 7 laptop, I got an error message: Windows cannot connect to Helen (my router's SSID). I have a strong connection.
The first thing I tried was the troubleshooting Windows provides, but of course that did nothing. It either said unknown error, or asked me to restart modem and router which I have done many times.
The second thing I tried was to connect it via ethernet cable to reduce the security again, but it refused to connect again with the same problem.
Now I don't know what to do. I've got a LAN connection to the modem (not the router!) at the moment.

[Asera]

Hard reset the gateway device and try the setting again.

[Dalinth]

I tried unplugging both router and modem for 10 seconds and plugging them back in to no avail. The exact error message is "Windows was unable to connect to Helen".
Also I noticed it makes no difference whether or not the router is actually connected to the modem; it displays the same error message.

[Eyad]

Is your PC selected to automaticly recive an IP adress from the router?

See if this does any help-- Wireless Configuration WINDOWS * Click Start * Click Control Panel * Select Network and Internet Connections * The Network and Internet Connections window will appear: Select the Network Connections icon * The Network Connections window will appear: Double click on Local Area Connection * The Local Area Connection window will appear: Select the General tab and click, or highlight Internet Protocol and press Properties * The TCP/IP Properties window will appear: * Make sure that both the Obtain an IP Address Automatically and Obtain DNS Server Address Automatically are selected, or checked.

~A guide after a quick google search!

Edit: Oh right you had windows 7 and that was for XP, but you might understand what I mean so you can find it yourself in Windows 7 else just reply and I can guide you

[Dalinth]

Yes, I've found many many MANY sources for XP as it apparently had interesting wireless bugs.
When I open Local Area Connection, there is no internet protocol:


I might note I had similar issues with a different router earlier, which was fixed by changing the SSID. However at the moment I have no access to the wireless router.

[Eyad]

I think you will find the right location when you hit Properties in that window

[Dalinth]

Yes, they are both set.

I also tried updating drivers, but online there are none for my OS, and Device Manager said they are up to date.

Edit: After Google diving a bit more, I finally found a source which advised me to delete the profile and reconnect. This has solved the issue.