Hello. I have Syncthing on a PC, and I can access the web GUI by opening syncthing.exe on my computer. However, trying to use the browser to connect to localhost:8384 causes my browser to report that it is unable to connect to the server. Closing out of the web GUI after using syncthing.exe on my computer, then immediately trying to reconnect, also causes the error. I use Firefox.
This may be related to the fact that my computer does not connect to my other device and sync with it unless the web GUI is opened, but this I put into a separate topic: Folders not syncing on PC unless web GUI is opened