You may have run into this when setting up a new smart home product: You’ve installed its companion app, created an account, plugged in the gadget, and you’re all ready to go until you realize it won’t connect to your Wi-Fi. What’s happening? You restart the app, the phone, your router, and try all kinds of other tricks to no avail. The app refuses to see or connect to your network. In some cases, you’re not given the courtesy of an error message; in others, developers are kind enough to point out the issue: 2.4GHz Wi-Fi.
The first time this happened to me, I was setting up the $1400 Roborock S7 MaxV Ultra. An eye-watering price didn’t save this robot vacuum from having a cheap Wi-Fi chip, and I was left wondering if it would ever work on my dual-band router or I’d have to return it. (Spoiler: it works, but that requires workarounds that I’ll get to later.)