MQTT broker blacklisted by Norton

[RGV250]

Hi,
I am trying to test the enviroment monitoring app developer out, all seems fine on the ESP side but when I launch the web app Norton sulks and throws a threat up saying it has prevented the connection to broker.hivemq.com because it is a dangerous website. Threat category URL:Blacklist

I have tried disabling Norton temporarily but it is still blocked?

Are there other options I could try, I am totally new to MQTT.
If I had local MQTT would Norton still complain. If not does anyone know if it is possible to install on ESP32 and is there an idiots guide.

Regards,
Bob

[chipfryer27]

Hi Bob

I don't think the ESP has enough resources to run a MQTT broker and I'm unaware of any designed to run on such. More or less any RPi can though and the WiKi documents an install of Mosquitto which I run on a RPi 3B. I documented setup in the forum and connection https://www.flowcode.co.uk/forums/viewt ... 419#p19419

I used MQTTX, CLI and FC charts to test. MQTTX is a PC app that acts as a client to publish / subscribe.

Norton should be able to whitelist HiveMQ if required but I haven't had any trouble connecting to HiveMQ and I use Norton.

Hope this helps

[BenR]

Hi Bob,

Reddit suggested this one.
https://flespi.com/mqtt-broker

Here's the thread.
https://www.reddit.com/r/esp32/comments ... tt_to_use/

Googling this and Google AI has suggested some ways to resolve the Norton block.
norton blocking broker.hivemq.com

[chipfryer27]

Hi

I haven't had any need, but you can whitelist from here

Screenshot 2026-01-16 095804.jpg (76.69 KiB) Viewed 384 times

In exclusions you can specify a website you know to be safe and trust.

Regards

[RGV250]

Thanks, I have it working of sorts, I am not sure why I needed to add to white list where temporary disabling Norton still blocked it?
Anyway, the next issue is the SHT31, all I am getting is -45 temp and 0 for humidity. Same values if not connected. I think it is a pin issue as my ESP32 seems different.
If I put fixed values in I get them on the trend so that side of things is working.

Regards,
Bob

[BenR]

Hi Bob,

Maybe try a software channel for the I2C and see if that's any better. Also what pins are you using the ESP32 has some pins which are input only.

[RGV250]

Hi,
I an not sure what the issue is but I have it working. I had to use a SHT40 (luckily I had one) and used software but on the hardware pins? (SCL GPIO22) (SDA GPIO21) on the device I have.
Only issue (thing I want to change) is the scrolling trend. I would like a Last xx readings where the one in the demo keeps on incrementing so the trend width gets smaller and smaller as time goes on.

Regards,
Bob

[chipfryer27]

Hi Bob

Further to above I thought I'd follow along and discovered Norton doesn't like "broker.hivemq.com" and I had to whitelist. Previously I hadn't used that address so never saw the issue until now.

This brings me to my next question. I have a free account with HiveMQ but according to my settings I don't use broker.hivemq.com it is instead a specific URL. Are you using a free account and if so is it using broker.hivemq.com ?

Regards

[RGV250]

Hi,
Yes it is broker.hivemq.com as that is what it is in the example. I will be looking at your post for a local one on the Raspberry Pi later as I think that will be the end device.

I am finding App developer quite a bit different, I thought I had found a getting started guide but cannot find it again.

Regards,
Bob

[mnfisher]

For interest - there is a MQTT server that will run on the esp32 - PicoMQTT. It is quite limited (5-10 connections) and so far I haven't managed to get it to run - but for 'remote' or low-power scenarios it might be a suitable alternative to the power of a RPi....

Having said which - a Pico is probably cheaper than and S3 so there might not be huge benefits to using it?

Martin