**Spectrum says it has to connect with ethernet.
Thanks for the info. How did the AirPort Express connect to your "old" modem/router? Wireless?
Keep in mind that the AirPort Express was designed more than 15 years ago and it used technology that was available at that time. The old....ancient actually....Express may simply not be compatible with newer Wi-Fi standards on the new Spectrum modem/router.
But.....we're willing to give things a try if you are willing to invest the time, and understand that what you are asking may not be possible.
We assume that you have performed the Factory Default Reset on the Express.....correct?
Temporarily for now, locate the AirPort Express in the same room as the Spectrum router for the setup
Power up the Express and let it run for a minute or two
Click on the Wi-Fi "bars" at the top of your Mac's screen
Look for a listing of New AirPort Base Station and click on AirPort Express just below that listing
AirPort Utility will open up automatically and if things look OK so far, AirPort Utility will suggest that the AirPort Express will be configured to "Join a wireless network"
Follow the prompts
Select the name of the Spectrum Wi-Fi network and enter the Wi-Fi password for the network
Give the Express a minute to try to set things up
A green light on the Express would be nice to see after a minute or two
Unplug the Express and move it to a location where it can receive a good Wi-Fi signal from Spectrum router and power up the Express. A green light would again be a nice thing to see
At this point, the Express should be set up and working correctly. Give things a try.
Please post back on your results. If you see a message about an "Unexpected Error" during the setup, it is not looking good.....but.....we'll try to use your iPhone again on another try at setting up the AirPort Express.