This article describes some known issues affecting Outlook 2011, Outlook 2016 and Outlook 2019 for Mac.

LDAP false error

When the Directory Server (LDAP) information is configured correctly in the account settings, the functionality is enabled for directory lookups, but Outlook will repeatedly display an error code 17768. We have contacted Microsoft about this and unfortunately, they do not have any working solution.
Workaround: Outlook 2011 SP1 (With autodiscover record in place) will download an offline address book. It will be listed as ACCOUNTNAME Directory. This is a 24-hour old copy of the global address list. Once in place, you can delete the directory service settings. Which will prevent the error from popping up again. This will also prevent direct GAL lookups.

Outlook prompts you for password after the computer wakes up after sleep

With Outlook open, use Finder to select the Applications folder, then the MSOffice folder, then holding the Control key down select the Outlook "O" icon, and select Get Info from the list.
 
Within the Get Info screen presented, check the Prevent Nap App box. 

14.3.2 update\Sent messages are being filtered

If you are experiencing this issue, upgrade to a newer version.

Server-side rules cannot be created

The only server-side rules that Outlook for Mac currently supports is Out of Office. It does not support setting server-side rules to move or manage messages and contacts or to act on calendar events. That means that all rules created in Outlook 2011 will be applied only when Outlook 2011 is running.
Note: starting with Outlook v.14.3.5, server-side rules are supported for Exchange Server 2010 SP1 and higher.

Exchange accounts are excluded when importing accounts from Mail app into Outlook for Mac

Exchange accounts are not included when you import data from Mail app into Outlook for Mac. To use your Exchange account, set up the account in Outlook for Mac.

Outlook for Mac does not support “direct booking” as Outlook for Windows does

Direct booking is a MAPI-only feature and Outlook for Mac uses Exchange Web Services. However, you can use Resource mailbox the same way as in Outlook for Windows. See the article Managing Resource Mailboxes.

Outlook for Mac does not support a way to replace signatures

Outlook for Mac does not support a way to replace a signature with another signature in the e-mail message automatically. When you add a new signature in an attempt to replace an old one, Outlook for Mac appends the new signature instead of replacing it. To replace the signature, you must delete the original signature from the e-mail message manually.

Calendar Sharing Within Outlook for Mac

Outlook for Mac users must be granted Reviewer access to another person's calendar to be able open that calendar and view details. If a user sets permission levels only to allow free/busy or free/busy limited details, an Outlook for Mac user will not be able to see any details of the shared calendar. PC users must grant Full Details to the Outlook for Mac user. Mac users must grant the Reviewer role to Outlook for Mac users. Basic free/busy time viewing is only viewable via the Outlook for Mac Scheduling Assistant feature, or via OWA.
Note: Outlook for Mac users who have a Reviewer role may also be able to select another users name within the Send As/From drop-down menu. Unless you have explicit permissions to Create Items within the selected users mailbox, Exchange will not allow you to send on the behalf of that person.

You can find some more information about Outlook 2011 sharing issues here.

Third-party applications that index content can decrease performance in Outlook for Mac

Third-party applications, such as Virex and LaunchBar, that index content on your hard disk may not recognize the new Outlook for Mac database. This can decrease performance in Outlook for Mac. To resolve this issue, if the third-party app allows the exclusion of certain directories, then include the Users/username/Documents/Microsoft User Data/Office 2011/2016/2019 Identities folder in the exclusion list.

Outlook for Mac does not synchronize with the Exchange Server mailbox master category list

Actions such as renaming a category might result in extraneous categories in other Exchange clients, such as Outlook for Windows and Outlook Web App. To resolve this issue, delete unwanted categories.

Mail, calendar events, contacts, tasks, and notes with categories created in Outlook for Mac synchronize with Outlook for Windows but might not keep their colors

At this time, while category names will synchronize, category colors do not sync. This applies to a user's primary calendar as well as delegated calendars.

Categories assigned to shared items are only for the benefit of the user who assigns them

If a user assigns a category to a shared item in a public folder or in a shared folder they will only be viewable on that one machine. Categories assigned to shared items do not sync to the Exchange server and will not be available for the same account on other computers nor will they be available to other users.

Contact photos do not sync with Outlook for Windows

Contact photos created in Outlook for Mac are not displayed after you synchronize Outlook for Mac with Outlook for Windows.

Recurring task dates may shift to other dates when viewed in different time zones

Recurring task dates may shift unexpectedly when moved across time zone boundaries.

You cannot run certain workflows

       The following workflows included with Office for Mac do not work:

  • In Excel, Import text file and create a table.
  • In Word, Send a PDF version in an Outlook message.
  • In Outlook, Send image attachments to iPhoto.

Notes do not display attachments in Outlook for Mac

If you move a mail message with the attachment to Notes folder, you will be not able to view it.

Downloading Attachments infinite loop

Outlook for Mac downloads all attachments in Inbox folder in batches of 20, and if you let it be, the process will eventually be finished. Although it may start over again, as Inbox is synchronized with the server more often than any other folder in Outlook for Mac.

Take the following steps to fix the issue:

  • Mark all messages with attachments in Inbox as read and clear Folder Cache (Right-click the folder > Properties > Empty Folder Cache), then start downloading items again.
  • Inbox should contain as few items as possible, 3000-4000 is the recommended maximum for Outlook for Mac. Sort the items by attachment size and move them into separate folders. Read the Knowledge Base article on Outlook For Mac: Best Practices for more information.
  • Move subfolders up so they are on the same level as Inbox, Sent Items, etc.
  • If the issue persists after taking the steps above create a new identity.

Outlook 2011 cannot connect to a POP/IMAP mailbox

A recent security update included disabling SSLv3, and this causes connection issues between Outlook 2011 and AD Postfix servers where POP/IMAP mailboxes are hosted. The issue doesn't affect Outlook 2016/2019.

Contact Groups cannot be synced

Contact groups created in Outlook for Mac are stored locally and can not be synchronized with the Exchange Server.
Contract groups created in OWA also can not be synchronized with Outlook for Mac.

Appointments are shown in the UTC time zone (Exchange 2010 only)

Accordring to Microsoft, the issue can be fixed only by upgrading to a later Exchange version. A fix isn't available for Exchange 2010.

Cannot send Calendar Invitations on behalf of Public folder in Outlook 2016/2019 for Mac

Outlook 2016/2019 for Mac does not support allowing subscribed Public Folder users to send on behalf of that Public Folder calendar. Users can send meeting invitations from their own Exchange account and can include that Public Folder as a recipient.

Outlook for Mac does not support Auto-mapping of shared mailboxes