Using the AirPort Utililty I put the remote AirPort into Bridge mode. Apparently this turns off the wireless function. Hmm... that shoots my idea in the foot.
Not sure what you are doing, but configuring an AirPort in Bridge Mode will normally not turn off the wireless function unless other settngs are adjusted as well.
when I choose "Extend a wireless network" (just experimenting), when I choose the wireless network created by the main AirPort, an error message pops up in the AirPort utility: "The wireless network you selected cannot be extended". Why?
If you forgot to enable the option to "Allow this network to be extended" on your "main" AirPort, you would certainly see this type of message.
If you need more help, we need to know what version of AirPort Utility you are using to configure the devices. Open AirPort Utility, click the AirPort Utility menu in the upper left corner of the screen, and click on About AirPort Utility.
An extended roaming network is what the Extremes are designed for - have faith - once configured properly they work great - I assuming that your DSL modem is only a modem amd not a wireless router so try this link - http://support.apple.com/kb/HT4259 - if this is not the case post for a different solution
"I understand this to mean that user iXod wants to connect the two AirPorts using wireless only, so hopefully he will clarify."
Yes, this is what I want to do. I want to connect a few Macs via ethernet to a second, remote AirPort Extreme, and link this 2nd AirPort to the primary AirPort Extreme via wireless.
Is this possible?
What you want to accomplish is doable.....if the "remote" AirPort Extreme is located where it can receive a good wireless signal from the "main" AirPort Extreme.
When an AirPort is setup to "Extend a wireless network", it provides more wireless coverage in the area where it is located and the Ethernet ports are enabled on the AirPort, so Ethernet devices can be connected to the LAN <-> ports.
But.....you need to understand that the "Ethernet" connection is only going to be as fast as the wireless connection between the two Airports will allow. Typically, wireless might be 130-250 Mpbs or so, while Gigabit Ethernet will be 1,000 Mbps.
Obviously, there is no way that the Ethernet devices on the "remote" AirPort will connect at 1,000 Mbps if the wireless connection between the AirPorts is only allowing 130 Mbps.
I got around to working on this again today.
FYI, I updated formware on both Airports to 7.6.1, the current version.
Following instructions, I enabled the 1st Airport: "Allow this network to be extended". Then I rebooted this Airport.
I then configured the 2nd Airport's Wireless setting thus; "Extend a wireless network". In this pane I chose the name of the wireless network created by the 1st Airport. I got this pop-up message: "This network cannot be extended." I rebooted this Airport, but no joy.
I tried this, and that, but there seems to be no way I can see to get past this error message.
If you have enabled a Guest Network on your main AirPort Extreme....and you are tyring to extend that netowrk.....it cannot be extended. Only the "main" wireless network can be extended.
Otherwise, your settings appear to be correct. your can verify them again using this Apple support document:
This type of configuration does work....I'm doing it right now and many other users have done this correctly.....so if you continue to have problems, I would take the AirPort Extreme to an Apple Store or Apple servicer to have them check over the device.
Thanks for your reply Bob,
The main Airport does have a guest wifi network, but I'm trying to extend only the main wifi network in this Airport.
I had not tried resetting (pushing that tiny button on the back with a paper clip) the Airport, so I'll try that before taking down the network to have Apple experts look at them.