"unexpected error" when setting up airport express to extend wifi

To help you we need the full details of the network.

Please answer question by question.. if possible screenshots make this a heck of a lot easier for us.

1. What is make and model of the main modem?

2. Is it working as router or pure modem?

3. What model is your Time Capsule? (An airport extreme has no hard disk so that is impossible).

This is where screenshots help loads.. give us screenshot of the summary page to start with.. just click the icon of the airport extreme in the airport utility and post showing the summary.

4. What model is the express?

5. Are you attempting to use it by ethernet or wireless?

Edit.. Also agree with Tesserax.. start your own post .. keeps it specific to your setup.

I have tried from my iPad Pro, iPhone 8, MacBook Pro and MacBook Air. I get the same error every time. Starts setup then gets to "reading old settings" next thing you know "An unexpected error occurred. Please try again." I've tried to make it my main router as well. Resetting it 100 times. Same error every time. It used to work (airport express). Now only the Airport Extreme 2TB works.

Two things:

1. This post is over a year old. I suggest that you start a new one so that it gets the attention that it deserves.
2. Provide as much detail as possible about your current network configuration, what you are trying to do, and what you have tried, yourself, to resolve it.

I have the same problem, and I cannot get my Extreme to join the network using Airport Utility on either the iMac or iPhoneX. Is there a way of updating the firmware?

The AirPort Express can only wirelessly "extend" the signal from another Apple wireless router.

So, the first troubleshooting question to ask here would be......is your main router also an Apple product?

If yes, what model of Apple router do you have?

Is your Mac still running the older 10.5.8 operating system that you list in your tagline?

Do you have a recent model iPhone or iPad that you could use for the setup?

Thanks for the info.

Power off the AirPort Extreme, wait a minute or two, then power it back up.

Move the AirPort Express into the same room or close proximity with the AirPort Extreme

Power up the Express for a minute or two, then hold in the reset button on the back of the Express for 7-8 seconds. Release the reset button and allow a full minute for the Express to restart to a slow, blinking amber light status.

Run the setup again using your Mac to see if the Express will set up correctly. If it does, move the Express to a location that is about half way between the AirPort Extreme and the general area where you need more wireless coverage. The more that you have line of sight between the AirPorts, the better the network will operate.

If the set up fails, then repeat the same steps as above, but use an iPhone or iPad for the setup. To do that.....

Go to the Home Screen on the iPhone / iPad

Tap Settings

Tap WiFi

Tap on AirPort Express under the heading of Set Up New Base Station

If the setup still fails with the iPhone or iPad, you likely have a defective Express

Had the same problem as stephaniefromtacoma. Was able to complete set up with an iPad. Many thanks.