@mature adult…You’d know if you were using a VPN, as they don’t happen by accident.
If you are interested…A VPN or ‘Virtual Private Network’ encrypts internet traffic, making it private. It is a legitimate business security tool.
It can also be provided as a service by a third-party company. They’ve had a very clever marketing spree over recent years; convincing people they need a VPN to stay secure on the internet. In fact, these days, internet traffic is usually encrypted anyway, so it is debatable if a VPN service adds anything here. There is a second factor in play, however.
If used via a VPN service provider it also has the effect of hiding your location, as when the traffic reaches its destination it looks as though it came from the VPN provider. Consequently, naughty people sending spam can use a VPN to hide their true location. I suspect BT’s mail system is set up to block their use because of this.
