Secure Wi-Fi connection

Turn off VPN and test.

Quote:

1. If the website requires a VPN connection, make sure it’s functioning properly.
2. See Connect your Mac to a VPN.

https://support.apple.com/guide/safari/if-you-cant-open-a-website-ibrw1071/mac

Apple routinely complains about poor WiFi security for anything encrypted less efficiently than WPA2. This is a notice only, as there are many situations like yours at Home Depot, where WiFi is purposefully unencrypted so that customers may freely use it. This is why many people like you use VPN to provide protection when using unprotected networks. This is how it should be.

Does your Home Depot WiFi access point have a Terms and Conditions page that you must pass through before you can use their service? This may very well be your problem. Although you have a solid WiFi connection, Home Depot's router will not allow you to pass any traffic until you agree to their terms of service.

Try this: With your VPN disengaged, connect to Home Depot WiFi. Open Safari. If you are greeted by a Home Depot welcome page, do what it says. Soon you should be released to your Safari browser's starting page, at which time you are connected. Try visiting somewhere like www.google.com. Engage your VPN and enjoy your life. Good luck.

You got to the sign-in page simply by waking up on the store's WiFi hotspot. Whenever a device shows up on the hotspot, the first browser request is diverted to the page. There is nothing you need to do to make this happen except for opening your browser as the first thing you do when you connect to the network. Before you engage your VPN, of course.

You will need to determine how long you can be away from the network before it forgets that you are already signed in. Some hotspots will remember users for the remainder of the calendar day, and some will remember for a couple of hours of absence. If stuff stops working, you need only to disengage your VPN and open your browser.

Enjoy.

That Safari “cannot establish a secure connection” error message is not a Wi-Fi message, and not related to Wi-Fi. That’s likely the target website, or the add-on VPN causing problems.

There is another insecure Wi-Fi message around; that {WEP, WPA, or WPA2 TKIP} is not considered secure.

Recommended settings for Wi-Fi routers and access points - Apple Support

That’s typically an old or poorly-configured Wi-Fi router.

What’s the exact error message?

What you’re reporting is pretty close to this: If Safari says it can't establish a secure connection, or the website is using weak encryption - Apple Support Which is usually a website issue, though VPN connects can cause problems here too.

If you’ve interested in privacy, remove the add-on VPN.

Pragmatically, it’s the store’s local IT or corporate IT that gets to fix this.

You get to disregard the diagnostic, pending any fix.

I’d think that a company that has had an expensive security breach would want to work toward better IT security, so you will want to discuss this with your manager.

Switching the administrative Wi-Fi network to WPA2 AES minimally, to WPA2/WPA3 transitional, or to WPA3, as these three are generally considered secure.

The guest network is another discussion; whether that would be unencrypted or WPA2 AES. I wouldn’t bother with WEP, WPA, or WPA2 TKIP, there. Either secure that guest network, or open it up to all. And pretty much any portable Wi-Fi device can now access at least WPA2 AES networks.

For those unfamiliar:

https://www.bsigroup.com/LocalFiles/en-US/Case-Studies/bsi-lessons-learned-home-depot.pdf

https://cgscomputer.com/home-depot/