• Outlook For Mac Not Compatible With High Sierra
• Outlook For Mac High Sierra

Important: Until Apple's next macOS release, expected in the Fall 2020, macOS 10.13 High Sierra is still supported on Microsoft 365 for Mac and Office 2019 for Mac. Both Acrobat 2017 and Acrobat DC are compatible with the new macOS High Sierra (10.13). Below are a few known issues. Adobe is trying to fix these issues in a future release. When you upgrade to the latest version of macOS 10.13.4 or launch Acrobat DC or Acrobat Reader DC for the first time on the.

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Original KB number: 3146087

Symptoms

You use Microsoft Outlook 2016 for Mac or Outlook for Mac 2011 to connect to a mailbox on a Microsoft Exchange server. When you send an email message that contains a large attachment, you receive the following error messages in Outlook for Mac.

Or, you receive a non-delivery report (NDR) in your Inbox like this one:

The message contains diagnostic information for administrators, such as the following:

Remove Server returned '500 5.2.11 RESOLVER.RST.SendSizeLimit.Sender; message too large for this sender'

Cause

This issue occurs when you send an email message that's larger than the Exchange Web Services (EWS) message size limit that's configured on the Exchange server.

Outlook For Mac Not Compatible With High Sierra

Resolution

You can increase the message size limit on the Exchange server to allow for larger email messages to be sent from Outlook for Mac clients and other EWS clients. For more information, see the following TechNet articles as appropriate for your version of Exchange Server.

Exchange Server 2016 and 2013: Configure client-specific message size limits

Exchange Server 2010: Set message size limits for Exchange Web Services

More information

For more information about this issue, see the following article in the Microsoft Knowledge Base:

3107326 You can't send large attachments by using the EWS client

Reading Time: 6minutes

Pre-Flight Check

• These instructions are intended specifically for setting up a new email account in Microsoft Outlook 2016 for Mac OS X 10.11.3.
• If you have not already created an email address on your server, visit our New User Tutorial: Creating E-Mail Addresses in cPanel.
• If you need to configure your email address in Outlook 2016 for Microsoft Windows, see How To Set Up Email in Outlook 2016. For other mail clients, check out our tutorial on setting up other email clients.

Step #1: Add or Edit the Email Account

1. To set up a new email account or edit the settings on an existing one, click the Tools menu and then select Accounts to open the Accounts panel.
2. The setup process is slightly different depending on whether you have any existing email accounts configured in Outlook 2016:
   • Setting up your first email account: If this is your first time setting up Outlook 2016, you will need to click on the envelope icon next to the third option: Other Email (iCloud, Google, Yahoo!, or other accounts):
   • Setting up an additional email account: Once any email account has been set up in Outlook 2016, additional accounts can be added by clicking the plus sign in the lower left corner and selecting Other Email… from the pull-down menu:
   • Changing the settings for an existing email account: Click on the account’s name in the account list on the left to make changes to any existing account in Outlook 2016, and skip ahead to Step #4: Editing an Existing Email Account.
     Note: You cannot edit an existing email account to directly change its connection method. To change an account from POP to IMAP or vice versa, simply add a new account for the email address as described below and select the desired connection type. Outlook 2016 will allow you to have multiple accounts for the same email address, so an account for sample@example.com using IMAP can coexist with an account for sample@example.com using POP. To prevent data loss, do not delete the existing account before adding a new one.

Step #2: Configuring a New Email Account

On the account information panel, enter the information as follows:

• E-mail address: requires your complete email address, such as sample@example.com.
• Password: is the password associated with the email account.
• User Name: is your full email address. It should exactly match what you entered into the E-mail address field above.
• Type: you may select IMAP or POP. IMAP is recommended for its ability to sync messages between multiple devices (to learn more about the difference between the protocols, see IMAP vs POP3 email).
• Incoming server:
  • When using standard (non-SSL) settings, use mail.yourdomainname.com
  • When using secure (SSL) settings, use the server’s hostname (host.yourdomainname.com)
  • The default port numbers should not need to be changed unless you have configured your server to use non-standard ports (not common)
  • Check the box next to Use SSL to connect (recommended)
• Outgoing server:
  • When using standard (non-SSL) settings, use mail.yourdomainname.com
  • When using secure (SSL) settings, use the server’s hostname (host.yourdomainname.com)
  • The default port numbers should not need to be changed unless you have configured your server to use non-standard ports (not common)
  • Check the box next to Use SSL to connect (recommended)

Once you’ve entered all the requested information, click the Add Account button at the bottom of the window to create the account with your specified settings.

Step #3: Configure Security Settings

When you add your email account, an alert window may prompt you to review security settings. This is expected if you have not already purchased and installed a signed, third-party verified SSL certificate on your mail server. If you see no such prompt, then you’re all set and can begin using Outlook 2016 with your email account immediately.If you do get a security prompt, which specifies that information that you view and send will be encrypted, note that Outlook 2016 will not be able to verify the security of the certificate through a third-party because you are the only authority validating it:If you wish to proceed with the connection, you have two options:

• You can click the Continue button to proceed, with the caveat that you may need to accept the warning each time Outlook connects.
• Or, you can permanently store the certificate and treat it as trusted, by clicking Show Certificate and then checking the box next to Always trust … before clicking Continue. You will need to authenticate with your password to store the exception for your self-signed certificate.

Outlook For Mac High Sierra

Once connected, Outlook 2016 will download your mail from the server along with any custom directories you’ve added, which will be synced by default.

Step #4: Editing an Existing Email Account

To change the settings on an existing email account, click the Tools menu and then select Accounts to open the Accounts panel.Click on the name of the account in the left pane, and make the desired changes:

• User Name: is your full email address. It should exactly match the value of the E-mail address field above.
• Password: is the password associated with the email account.
• Incoming server:
  • When using standard (non-SSL) settings, use mail.yourdomainname.com
  • When using secure (SSL) settings, use the server’s hostname (host.yourdomainname.com)
  • The default port numbers should not need to be changed unless you have configured your server to use non-standard ports. If you do need to configure mail on a different port, you can check the box next to Override default port and enter the appropriate incoming mail server value (POP3 should be 110 for non-SSL connections and 995 when using SSL; IMAP should be 143 for non-SSL connections and 943 when using SSL.)
  • Check the box next to Use SSL to connect (recommended) for a secure connection.
• Outgoing server:
  • When using standard (non-SSL) settings, use mail.yourdomainname.com
  • When using secure (SSL) settings, use the server’s hostname (host.yourdomainname.com)
  • The default port numbers should not need to be changed unless you have configured your server to use non-standard ports. If you do need to configure mail on a different port, you can check the box next to Override default port and enter the appropriate outgoing mail server value (25 for non-SSL connections and 465 when using SSL; Unlike many other mail clients, Outlook 2016 does not require you to use port 587 on Mac OS X).
  • Check the box next to Use SSL to connect (recommended) for a secure connection.
  • The More Options… button will allow you to configure authentication for the outgoing (SMTP) mail server:
    • Authentication: Typically, Use Incoming Server Info is sufficient, but if you receive connection errors due to SMTP authentication, you may need to select User Name and Password. Do not select None; you will not be able to send mail if None is selected as the authentication type.
    • User Name: This field can only be filled in if you use the User Name and Password authentication type. If enabled, it must be the full email address.
    • Password: This field can only be filled in if you use the User Name and Password authentication type. If enabled, use the email account’s password.

Bonus: Select IMAP Folders to Sync

By default, Outlook 2016 for Mac OS X will sync all IMAP folders. To specify which ones you want to sync, pull down under the Tools menu and select IMAP Folders… to bring up the Folder Browser.In the Folder Browser, you will see a list of your accounts in the left pane.

• In the first pane, click on the IMAP account’s name
• In the second pane, click on INBOX (or the desired custom folder, if listed)
• In the third pane, click on the folder to which you want to subscribe or unsubscribe.
• Folders to which you already are subscribed will be displayed in bold type, while folders to which you are not currently subscribed will be displayed in a light-face font. Note that on some versions of Mac OS X, the distinction can be almost imperceptible.
• Clicking on the name of a folder to which you are subscribed will allow you to click the red ( – ) Unsubscribe button in the top-left menu, and clicking on the name of a folder to which you are not subscribed will allow you to click on the green ( + ) Subscribe button in the top-left menu.
• You can not unsubscribe to default account folders, such as Drafts, Junk, Sent, and Trash.