I set up my brand new GL-MT300A at home, I bought a case for it, and I went on a trip. Having arrived at a hotel put a LAN cable into the GL-MT300A LAN port and connected the USB for power.
No Wifi signal is visible to any of my devices, the green lights are on, but no Wifi.
If you have an Ethernet cable and a PC you should be able to connect to the devices LAN port and manually reset the wireless config.
The easiest thing is to go to Advanced Config at the top right and log into Luci. Goto Networking => Wireless and select the STAtion (Client) and “Remove”, then OK. Wireless should restart and you can then connect to the new STAtion, probably with out rebooting. Use the GLi GUI to connect to the new STAtion. Its much easier to use than Luci for this.
You may be able to just go to the GLi GUI and scan for a new STAtion, but I am not sure.
If you have customized your settings (IP, AP credentials, etc) you may want to make a backup of the settings and keep this on a USB drive. You can then reset the device and restore the settings. You probably want to leave the wireless STAtion unconfigured. If you installed packages, these will need to be reinstalled or some functions will not work.
On a WISP connection: when I switch (while on a wifi connection, not LAN) from one wifi access point to another, it works, but when I switch back, it doesn’t, see image attached.
I can switch back to the original wifi access point only when I am connected through LAN.
I would like to switch back and forth while on wifi.
I get those same types of errors when I use WISP. Sometimes it works, some times it doesn’t. I often have to do a full factory reset if I want to connect to another access point.