
WHY OUTLOOK 2016 FOR MAC DO NOT MARK EMAILS AS READ ON SERVER FOR MAC
When you connect to an Exchange 2013 or a later version mailbox (including Exchange Online), Outlook 2016 for Mac does not let you add safe senders. Because Outlook 2016 for Mac doesn’t perform any junk mail filtering, client-side safe senders no longer have any use. When you connect to IMAP, POP or an Exchange 2010 mailbox, Outlook 2016 for Mac lets you add safe senders. However, safe senders are client-side only and don’t synchronize to the server. Under the Outlook menu -> Preferences -> Junk in Outlook 2016 for Mac, there is no Junk Email Protection Level setting.

Junk filtering is when email headers and content are scanned for characteristics that makes the email message likely to be junk. When you add an email address to the Blocked Senders list, email messages from that email address are always moved to the Junk E-Mail folder. It’s important to understand that junk mail filtering and blocked senders are not the same thing, although they are frequently used in conjunction. This behavior makes client-side Outlook junk filtering redundant. Exchange servers provide server-side junk mail filtering, and most popular email providers, such as Hotmail,, Gmail, and Yahoo, provide server-side junk mail filtering. Email messages are not scanned client-side by Outlook 2016 for Mac to determine whether they are junk mail. Instead, it only relies on the mail server to perform all junk mail filtering. Outlook 2016 for Mac doesn’t provide any client-side junk mail protection for any kind of an account (Exchange, POP, or IMAP).

Client-side junk filtering occurs on the client (such as Outlook and Outlook for Mac) when email messages are downloaded from the server to the client.

Server-side junk filtering occurs on the mail server (such as Exchange) as soon as email messages arrive in the mailbox. There are two kinds of junk mail filtering (sever-side and client-side). This article discusses how Outlook 2016 for Mac handles Junk Email Protection. Outlook for Microsoft 365 for Mac Office for business More.
