The proper method is to locate the reset button (hole) on the rear panel of the unit. With the router powered on, use a paperclip to hold the button down for 10 seconds. Release the button and the router will go through its reboot process. Wait about 30 seconds to access the router. The default IP address is http://192.168.0.1 (enter this in your browser address bar). When logging in, the username is admin and leave the password box empty.
Since you have the manual all you need do now is log in to the configuration on the router (as indicated above) then make use of the manual from where it mentions CONFIGURATION somewhere around page 13 (can't be more precise as you didn't mention which of the 4 revisions of the router you actually have. Absolutely no need to be messing around with any CD.
I read my manual and went through all the procedures and after resetting when i inserted the disc to Re-setup everything. IT KEEPS ASKING FOR MY OLD ROUTER PASSWORD WHICH I DONT KNOW.
Believe me I have tried every single combination but still no success.