How do i put a password on my D-Link DIR 600 i want to use it private. pls help me.. tanx

D-link DIR-600 default username is admin and password is NULL (blank).
after u login go to admnistration tab and change password there

DIR-600 Default Password & Other Default Login Data Version Default Username Default Password Default IP Privileges Al admin [none] 192.168.0.1 Administrator

Hello marticarpio
As far as a password i'm going to have to assume you mean to log into the router, past that security goes by pass phrase.
to log into your router open up a web browser(Internet explorer) type 192.168.0.1 At the log on screen type Username: admin Password:(default is blank) if a password other then the default is on the router, and you do not have it. use a paper clip to press in the reset button on the back of the router for 15 seconds. repeat the log in instructions using the default password. Immediately change the default password.
If you wanted to have a secure wireless network, click the wireless settings section. Name your router, and select a type of security. Depending on the type of security you choose follow the onscreen directions(wps may be easier)