Everyone who runs an email server knows Microslop doesn't care about receiving its customer's emails. The best thing you can do is migrate away.

Keep a few throwaway Hotmail/Outlook addresses in your password manager, in case you need to use a Windows PC that demands a Microslop account. That's about the end of their usefulness.

Just like Internet Explorer used to be the program you used once -- and only once -- to download a proper browser.

No worries. If you migrate your email server to Azure(TM) the delivery is guaranteed.