Hello,
I recently moved. I used to have my Airport Express set up to extend my Airport Extreme Network. All was working fine. Several months before moving, I did upgrade software to Lion and the AirPort Utility 6. So, after moving, I can not choose the option to "allow this network to be extended" - it it missing.
Just like you recommended in the above responses, I did download the Airport Utility 5.6. Even when I run it, the option is still not there. I have tried holding the command key when trying to make the selection also, but that did nothing either. I don't understand why my option has disappeared - it even discusses it in the help section for the 5.6 utility. I tried installing the utility (5.6) on both my mac mini and my big mac - it isn't showing up as an option in either.
Any help you can give is greatly appreciated!
Thanks