Changed Router Firmware And Password / Now Laptop Won't Connect

My son decided to update our router firmware, together with this the password was changed. My computer which hosts the Internet connection works fine, all other laptops have now been connected successfully after simply changing the password. However my wifes laptop won't play ball. It is a Samsung R510, with Vista Home Premium OS. It worked fine prior to updating the firmware. I have been through the process of changing the password and have the correct security encryption in place, exactly the same process as with the other laptops.

It then says successfully connected, but shows in the bottom right of the screen, Unidentified network access local only and will not connect when the browser is opened. I have tried to diagnose but the usual windows prompt to reboot both modem and router has no effect. I have set it to private, as advised elsewhere, I have switched the firewall off and removed security software, all to no avail.

I tried the command prompt, then ipconfig/renew. An error occurred while renewing interface Wireless Connection: unable to contact your DHCP server. Request has timed out. No operation can be performed on Local Area Connection while it has media disconnected. Let me stress that no changes were made to the laptop at all, it is simply not connecting following the firmware update and password change. All other computers, and phones, 6 in total, are all working fine from simply changing the password.