Odd WiFi Problem

[SpeedThree5500]

My wife took her 2019 MB Pro running the latest version of Ventura to a genealogy center to do some research. She successfully logged on to their network by entering the network name and password but then, after opening Firefox was unable to access any website. She restarted and tried again and again could not connect: the gearwheel would spin and spin w/ no result. However, there were numerous other Mac computers at the center that were successfully logging on to websites using the Chrome browser. My wife tried to go to Google.com, Apple.com, etc., sites to which she had often gone in the past and all timed out. She of course could not get to the Google site to d/l Chrome. Management at the center could only speculate that there must be some setting on her computer that was preventing her from loading any sites.

I took her Mac and connected to our neighbor's WiFi and was able to load any and all sites.

Anyone have any idea what might have caused this. What setting she might have inadvertently "tripped" to cause this?

Many thanks as it is a complete mystery to me.

 

[MacInWin]

Take a look at her DNS settings. System Settings/Network, click on the WiFi, then on the network she is connected to, and then Details. Look at what's under DNS. If there are no entries, her system is dependent on the ISP to provide DNS service (decode the "name" of the website to the "numbers" of the website for navigation to it. Some good DNS services are 1.1.1.1, 8.8.8.8 and 9.9.9.9. The first one is from Cloudflarre, the others are, I think, Google DNS servers. To add them, click on the "+" below the DNS Servers box and then type them in.

EDIT: Correction, 1.1.1.1 is CloudFlare, 8.8.8.8 is Google DNS, and 9.9.9.9 is Quad9 DNS server.