Wemos d1 mini module with Tasmota does not connect to mosquitto - possible causes

Maybe someone could give me some advice. I have a Wemos d1 mini module, I have uploaded Tasmota. The module connects nicely to the WiFi network, I can access its interface. You can issue commands in the terminal, it responds. Mosquitto is installed on the computer, and it works. I can subscribe to a topic using mosquitto_sub and publish using mosquitto_pub, and it works nicely. My Tasmota, on the other hand, is unable to connect to mosquitto. Every 10 seconds it writes: attempt to establish a connection, followed by: connection failed. I'm a beginner in these blocks and don't know what else I can try. Something wrong with the module? The WiFi access point is blocking something? mosquitto requires configuration? (It runs as a service on Windows, I haven't configured anything) Something with the Windows firewall? Apparently disabled.

Thanks in advance,

MAciej

Obviously in Tasmota given the correct IP address of the MQTT broker?

Yes, all the obvious has clicked. The correct IP address and port. One thing I left out was the user/password. As far as I know, this is optional.

Greetings,

MAciej

Try sending something to the MQTT server from another machine on the same network. E.g. using an android phone.
If you have the firewall on Windows turned off then it should connect. I have never had a problem with this, admittedly my server is not on Windows. If you do have the firewall turned off, add a rule to allow incoming and outgoing connections on port 1883, as I guess that's the port you have set up?

The matter cleared up a bit. I installed the same mosquitt on a raspberry on the same network, and communication started immediately. Conclusion: the lift is blocking communication despite the firewall being turned off. This is not a big surprise. I'll dredge this up some more, but for now the problem is solved. The broker was ultimately going to be on a raspberry anyway.
I'm back to playing around and thanks for your interest.

Maciej