Change wifi details AFTER first boot on a headless dietpi (no KVM)

So I’m at my parents for a few days. I grabbed my RPi model B (original) with a USB wifi dongle, running dietpi from my house before leaving, but I forgot any accessories and they have no keyboard mouse or spare HDMI monitor/TV to use and their Wifi details are different to mine (obviously). I have my laptop (with an SD card reader) and an Ethernet cable, but for some reason the Pi didn’t DHCP and get an IP address after it was plugged directly into the router.

How can I change the WiFi settings on the SD card (in my laptop) so my RPi will connect to the new wifi network? I tried re-adding the “dietpi-wifi.txt” file with what I think was the expected format, but I gather that is not going to get re-read after the initial boot. Is there any way on the boot partition (that is visible to windows) to change the wifi details and have dietpi apply them next time the Rpi boots?



many thanks for your question. You would need access to RootFS (ext4) to be able to change WiFi details. Usually WiFi details are located at /etc/wpa_supplicant/wpa_supplicant.conf