Let's get this sorted out instead of shilly-shallying around. First of all VM are not responsible for sorting out problems with your email program. That is your job. VM provide email as a free/value added service as part of its offer. As long as your web mail works VM have done their bit. Now it just so happens that VM do publish instructions about how to set up email programs, but that is the limit of the help they will provide.
However your description of the issue shows the classic symptoms of having a spambot on your system which unbeknown to you is hijacking your VM connection to send spam. It does NOT do this through your email program so you will never see it. But what it is doing is polluting the internet with spam. So we are all suffering when this happens.
If spam is detected as coming from your system by independent third parties VM will not allow you to send email via an email program until you have cleared the infection from your system. End of story. Moan all you like but that is how it is. The problem doesn't affect sending via web mail because VM don't apply the same checks to that system as they do when you use an email program. Again that is how it is.
The instructions you were pointed to provide the only secure way of tracking down which device on your network at home is spending this spam. More about this in a minute. However they do require a bit of application and a willingness to step outside your comfort zone. Analogy - your car breaks down, its a Ford. What do you do, call a garage or call Ford and then give up on the car until Ford fix it? You call a garage or get a mate to help. It is your call and your responsibility to fix it. The "mate" you need for your mail issue is us here.
And if you do have a spambot on your system then changing ISP won't help. Empty threat. Most ISPs operate similar protective arrangements.
I'll guide you in simple steps to establishing in another way what might be going on. Your choice - follow the guidance and start to solve the solve the problem or sulk.
But before I do that the most common hiding places for spam bots are Amazon Firesticks which have been loaded with additional software most often for "free" TV services, using a VPN called Hola (free edition), Android phones connected by wifi. Any of these are easily infected or infectious and need sorting out. If it is a side loaded Firestick full of unauthorised software it needs resetting to factory condition.
So the steps - and follow them to the letter. If you provide more information than asked for you will be putting your privacy at risk.
Step one, click on this link:
https://whatismyipaddress.com/
Make a note of the entry opposite IPv4. Keep the numbers to yourself.
Then go here:
https://www.spamhaus.org/lookup/
Where it says "Enter an IP address", put those numbers in. Make sure you copy exactly, numbers and the full stops.
Report the result here. What we are looking for is whether the result says listed on SBL and its sub list SBLCSS. Nothing else matters. And I mean that. So don't tell us anything other than the answer to the question I have asked.
This will show whether you have a spambot. It might also show that we are pursuing a red herring. Either way we know what to say next based on the results you get.
Hope you can manage this? It really is very easy. And you don't have to worry about what any of it means - leave that to us. That's why we come here to help.
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