Not 100% sure on your router,but underneath or on the side there maybe a reset pin hole... Disconnect from the mains,and press the reset,this will factory set the router enabling you to setup the encryption again.
Netgear routers, enter into your browser 192.168.0.1 This should bring up the routers access box where you will need to type user.. admin and password is password if the password has been changed and you cannot remember this, unfortunately you will need to reset your router to factory settings by holding the reset button on the rear of the router for 30 secs. you will however need to reapply your settings
No you will not need the disk it merely resets the router configuration to factory settings. you would loose any firmware updates and passwords.please confirm you are unable to access the router configureation.
when you attempt to access the wireless network it states it cannot. windows searches for a reason and states that it could not connect because the network was open (unsecure). vista gives you a list of options including manage network. when you access this it gives you a box regarding the wireless network with a gereral tab and a security tab. pressing the security tab shows a box with about 6 options. 1. open 2. shared 3. wpa 4. wpa 2 (can't recall the last 2 but they were security settings similar to wpa (wsk?)) shared and wpa were tried but both require password input. as he could'nt recall the password, open was chosen, allowing access to internet but obviously unsecure. On vista this is the only access to netgear configuration I could find.