Can't connect to internet anymore

I can connect to my router with a strong signal but doesn't connect to the internet.

It has been able to connect before and have no problems but sometimes it won't connect at all. When i look at network connections I don't even see where i can put in my internet password.

I use an airlink 101 router and primus internet. Macbook 10.4.11.

My other computers hook up wirelessly just fine so I know there's no problem with the router or the internet connection.

Hope someone can walk me through this,

Thanks,
John

 

Thanks alot. That worked.