Originally Posted by net

You must check your anti spam protection there if you do not want to block their IPs.

I use a side email hosting provider that uses own anti-spam. It doesn’t block all spams.

But I also do not want to do so. Sometimes legit good senders misconfigure their email services (like set wrong SPF and so), so in case I do not miss their emails on the company account, I do not want to enable advanced evil spam protections. I rarely get spam, except, Leaseweb.

My question is more about how to force Leaseweb to follow industry practices. I thought in 2022 blocking a customer that spamming is not a problem, especially, for EU companies (German subsidiary).

I investigated and proved that the entire owner of the account is spammer. But leaseweb still does not block it without any explanation.