In the AirPort Express Assistant, you can choose to use the Express as your main wireless gateway or as part of an existing network; the Assistant guides you through the options smoothly. Download Apple Airport Utility for Windows. Utility that allows users to configure an AirPort Wi-Fi Base Station to create a wireless network and manage a USB device (e.g., printer, external hard. The green light will flash for four times; this is the time when you should release the reset button, and the device will reboot. Wait for around 1 minute and then go on configuring your device with Airport Admin Utility or AirPort Express Assistant.

Networking >Apple Airport Express Setup

This pilot is now over. Thank you for your participation.
In an effort to provide students with access to as many types of technology resources as they wish, CUIT is conducting a pilot program, allowing students in Furnald, Hartley, and Wallach Halls to install Apple AirPort® Express wireless routers, fully supported by CUIT. If you own an Apple AirPort® Express wireless router, please follow the instructions below to set up your secure, wireless access point.
This is the only wireless router supported by CUIT*. If you need assistance, you may contact the CUIT Helpdesk by submitting a ticket request online, sending email to askcuit@columbia.edu, or calling the CUIT Helpdesk at 212-854-1919.
Remember: You are responsible for all network traffic on your port, traffic from your computer, or others using your access point. Therefore, never share your password. If your computer – or any computer using your access point is compromised or reported for a copyright violation, all computers will be reformatted.
*Bridging your wireless connection is not supported, nor is any other brand of wireless router.
Pilot Results: This is a pilot to determine if wireless network traffic in Residence Halls negatively impacts Columbia’s network. Should the pilot be determined successful, CUIT will expand the pilot to other Residence Halls. No other router will be supported.
FAQ

Apple Airport Express

To set up and configure your AirPort Express to use AirPort for wireless networking and Internet access, use the AirPort Setup Assistant for Mac OS X, or the AirPort ExpressAssistant for Windows XP. (The assistant is installed on your computer when you install the software on the AirPort Express CD or you can also download it from Apple.)
After unpacking your Airport Express, connect the ethernet cable from your jack to the ethernet port on the Airport Express. Plug the AC adapter into an electrical outlet.
Open the AirPort Setup Assistant, located in Applications/Utilities on a Macintosh, or the AirPort Express Assistant, located in Start > All Programs > AirPort on a computerusing Windows XP. Follow the onscreen instructions to configure and share Internet access on your AirPort Express.
Enter a Base Station Name and Password click Continue. Write these names down for future reference.
Select 'I do not have a wireless network and would like to create one' and click Continue.
Select WPA2 Personal security on the next screen, then enter a Wireless Network Name and Password and Verify it. This password must be between 8 and 63 characters. You should write this password down and keep it near your Airport Express in case you forget it. Click Continue.
Select 'I connect to the Internet with a DSL or cable modem using DHCP'. Leave the default settings (Using DHCP) and click Continue.
The next screen will review your setup information.Click Update. Your Airport Express station has been configured and will now restart. Quit the Airport Utility and connect to your new wireless network.

Open the AirPort Admin utility (found in the Utilities folder within the Applications folder).

Select your base station in the resulting window and click Configure. If asked to, enter the password.

Click the AirPort tab and choose a new channel from the Channel pop-up menu and click Update.

FAQ

Airport Express Assistant Download Mac Installer

Hi Folks,

I recently bought an old AirPort Express (A1088) on ebay for 20 Euros. These thingies are still a good working WiFi router and they support WPA2. However thanks to Apples policy “Do not support Hardware that is older than 5 years” it is not possible to configure it on a modern Mac because the Airport Utility does not support this hardware anymore. Thanks again Apple.

But Dr. Sven found out how to do it and here is the description. I found most parts of it here

Airport Express Assistant Download Mac Download

Reset the AirPort Express. While it’s plugged in, hold the reset button until the light starts flashing fast (about 10–20 seconds) then let go. After that the password – if you are asked – is “public”
Connect the AirPort Express to your computer with a LAN cable (configuring it wireless didn’t work for me)
Download this old version of the AirPort Utility 5.6.1 with an AppleScript that allows it to launch on macOS Sierra, and launch the dmg.
Drag AirPort Utility 5.6.1 into your /Applications/Utilities/ folder. You will need to enter your administrator password.
Next, after you’ve dragged AirPort Utility 5.6.1 into the Utilities folder, drag AirPort Utility 5.6.1 Launcher into your /Applications/Utilities/ folder. You may need to enter your administrator password again. It’s important to do steps 3 and 4 separately instead of dragging both into the folder at once — otherwise, you’ll most likely get an error message. This is the biggest area people run into problems with my guide.
Open AirPort Utility 5.6.1 Launcher package (ctrl. + klick and then show packe content). Then click through contents and MacOS and there you see the file “applet”. Double klick it. You may need to open Security & Privacy in System Preferences to approve this, if you get a message about the app being from an unauthorized developer. Now that the AirPort Utility is open you should be able to edit everything and it is all good.

Airport Express Software

After this you should be able to connect to your AirPort Express wireless too 🙂

Airport Express Download Mac

Cheers,
Dr. Sven