Problem with connection, router, airport

I have had a problem for a few weeks and I hope someone can help.

Whenever I shut down my computer for the evening and then log back in in the morning, i am having trouble getting a connection and end up having to unplug/replug in the router to get a connection again. Then everything is fine for the rest of the day, EXCEPT if I have to shut down my computer again for any reason---then I have to do the same thing again. I don't think it has anything to do with my snow leopard upgrade as I've only noticed this for the past 2 weeks, whereas I upgraded long before this. Everything else seems to be okay such as airport settings, etc.

Thank you,
drking

Mac OS X / Snow Leopard / 10.6.1
Linksys router ~ Airport

If you select 'join other network' and type the ssid and password does it connect? Try remove your network from preferred networks and add it again. To do this go to setting/network/airport/advanced.

EDIT: is it that your computer cant fid your network or the network itself fails for all computers?

Thank you. It seems the problem corrected after typing my router's network address into the address bar and entering my user name and password. I don't know why I hadn't tried this before but seems this fixed the problem. I will keep an eye out for any more problems. Thanks again!

drking