Show pagesourceOld revisionsBacklinksBack to top Share via Share via... Twitter LinkedIn Facebook Pinterest Telegram WhatsApp Yammer RedditRecent ChangesSend via e-MailPrintPermalink × This is an old revision of the document! Enabling SPF Check Exchange Admin Center→Protections→Spam Filter Set SPF record: hard fail: to On Last modified: 2018/02/25 01:18(external edit)