How to force users to change their mail address?

[XFFA.IR Bot]

When sending out notifications to users via mail there happen all kinds of bounces. Often, the mail address does not exist anymore or the mailbox is full or they have some weird forwarding to another mailadress which results in a SPF failure. I've activated automated bounce handling and set up a dedicated mail box for that. This works and users with hard bounces get the state "invalid mail address" applied automatically. So far so good. But what comes next?

Some of those are older users...

لطفا گزینه ورود یا ثبت‌نام را انتخاب کنید تا پیوندها برای شما قابل نمایش شوند