Need help with Apple Airport Express


I bought an Apple Airport Express so I can connect my Marantz SR-7007 to my wireless network. I want to use it as a wireless client. I have an iMac and AT&T uverse is my Internet provider. The Airport Express configures properly ONLY IF it is connected to the router with an Ethernet cable. I can not get it to work with the Wireless network. I've googled directions and tried everything. Can anyone help, or do I have to have an Apple tech come to the house ? Thanks
mabonn
You will find in System-Router menu: Setup, Wireless, Security etc..

Select Wireless. It will open Basic Wireless Settings, Wireless Security, Guest Access etc. Select Guest Access. It will show option "Allow Guest Access" Yes/No - select "No".

Guest possibly cannot change settings but I have no use for this option and disabled it.
Kijanki, Thanks. One more question..... I got it working for Internet radio, but the AE no longer accesses my iMac music library. The Squeezebox DOES access my iMac library. ?? Thanks for your help. .. Matt
Not sure. When I select "Media Server" from the network menu on the Marantz receiver, the screen says "empty". On the iMac, it says the Logitech Media Server is running. When I had the AE running wirelessly from the 2wire modem/router, the Marantz screen would say "Matt's Library", and allow me to access my library.
Now that you have the Linksys router up and running, you'll need go through the setup for the AE again to join the Linksys Wifi network.

Also, the AE only supports 44KHz output, so anything higher resolution gets down-sampled.