• Sep 02, 2015  Sign in. Download Microsoft Outlook for Mac for Office 365. From Official Microsoft Download Center. For people who already have Office for Mac 2011 and Outlook for Mac 2011 installed on their Mac, check out this help article for guidance. Follow Microsoft.
• May 20, 2019  This method allows Outlook for Mac to connect to the server even when SSL 2.0 and 3.0 are blocked. If you are using a security product such as Microsoft Forefront Threat Management Gateway (TMG) for managing connections to Exchange Server from outside your company, you will need to configure your TMG server using KB article 980436.
• Mar 26, 2020  If you're using Outlook to access your Office 365 email account or another Exchange-based email account, and you're having problems, we want to get you back to sending and receiving email as quickly as possible. We can diagnose and fix several common Outlook connectivity issues.
• In Microsoft Outlook 2016 for Mac, you are repeatedly prompted for authentication while you're connected to your Office 365 account. This issue occurs because of the presence of duplicate tokens in the keychain. To resolve this issue in Outlook 2016 for Mac, install the February 2017 Outlook update (version 15.31.0) from the.

• Sign In Microsoft Email
• Sign In Outlook
• Sign In Microsoft Exchange Account

Symptoms

Microsoft Support. Add and manage delegates in Outlook for Mac. Before a delegate can access your items, he or she must add you to the People I am a delegate for list in his or her Microsoft Exchange account. For information about how to become a delegate for someone else. Someone has granted you permission to access one of their calendars and you want to open it in Outlook 2016 for Mac. Here's how: Important: To open another person's calendar, both you and the other person must have a Microsoft Exchange account and the account owner must grant you permission.

In Microsoft Outlook 2016 for Mac, you are repeatedly prompted for authentication while you're connected to your Office 365 account.

Cause

This issue occurs because of the presence of duplicate tokens in the keychain.

Resolution

To resolve this issue in Outlook 2016 for Mac, install the February 2017 Outlook update (version 15.31.0) from the following Office website:

Workaround

To work around this issue, delete any cached passwords for your account, and also delete any modern authentication tokens from the keychain. To do this, follow these steps.

Note

These steps affect all Office applications that use modern authentication.

1. Quit Outlook and all other Office applications.

2. Start Keychain Access by using one of the following methods:

   • Select the Finder application, click Utilities on the Go menu, and then double-click Keychain Access.
   • In Spotlight Search, type Keychain Access, and then double-click Keychain Access in the search results.

3. In the search field in Keychain Access, enter Exchange.

4. In the search results, select each item to view the Account that's listed at the top, and then press Delete. Repeat this step to delete all items for your Exchange account.

5. In the search field, enter adal.

6. Select all items whose type is MicrosoftOffice15_2_Data:ADAL:<GUID>, and then press Delete.

7. In the search field, enter office.

8. Select the items that are named Microsoft Office Identities Cache 2 and Microsoft Office Identities Settings 2, and then press Delete.

9. Quit Keychain Access.

   Note

   When you start Outlook, you are prompted to authenticate.

Introduction

This article contains information about how to troubleshoot Lync for Mac issues in Skype for Business Online (formerly Lync Online). It also discusses how to sign in to Skype for Business Online by using Lync for Mac and how to collect log files and system information for Lync for Mac issues.

Procedure

Before you troubleshoot

First, make sure that users follow the correct steps when they sign in to Skype for Business Online. If users are signing in to Skype for Business Online correctly and the issue persists, use one or more of the other methods later in this article to troubleshoot the issue, as appropriate for your situation.

Note

To connect Lync for Mac 2011 to Skype for Business Online in Office 365, you must have Lync for Mac version 14.0.6 or a later version installed. If you use a version that's earlier than version 14.0.6, you may have problems when you sign in to Skype for Business Online because earlier versions have issues that prevent authentication to Skype for Business Online. You can find the latest update at Update for Lync for Mac 2011.

Make sure that users follow the correct steps when they sign in to Skype for Business Online

To sign in to Skype for Business Online by using Lync for Mac, users should follow these steps:

1. Start Lync for Mac.

2. Enter your email address, user ID, and password.

3. Next to Sign in as, select the presence status that you want to display after you sign in.

4. If you want to save your credentials, click to select the Remember my password check box. Your credentials will be saved in the Mac OS Keychain and will work until the next time that your password changes or expires.

5. To configure additional options for connecting to Skype for Business Online, click Advanced. You can configure the following options:

   • Automatic Configuration: In most cases, this is the correct setting. If the necessary DNS records are present and automatic configuration isn't working, try Manual Configuration.

   • Manual Configuration: Select this option if automatic configuration is failing, and specify the following values:

     • Internal server name: sipdir.online.lync.com:443
     • External server name: sipdir.online.lync.com:443

   • Kerberos authentication:Leave this option cleared. Office 365 uses the Microsoft Azure AD authentication system for authentication.

If you still can't sign in

The following table describes error messages that may occur when users sign in or use Lync for Mac with Skype for Business Online.

Troubleshoot Lync for Mac issues

Use one or more of the following methods, as appropriate for your situation.

Users may be unable to sign in unless they first use an incorrect sign-in address

1. Try to sign in to Skype for Business Online by using an incorrect sign-in address. That is, a sign-in address that you know won't work. For example, EmailAddress @contoso.com.

   Note

   When you do this, sign-in will fail. This is expected behavior.

2. After the sign-in fails, sign in by using the correct sign-in address. For example, EmailAddress@contoso.com.

If Lync for Mac stops working after an Internet connectivity issue, flush the DNS cache

To flush the DNS cache, do one of the following, depending on the version of Mac OS that you're running:

• If you're running Mac OS X 10.5, Mac OS X 10.6, or Mac OS X 10.7 Lion, start Terminal, and then run the following command: dscacheutil -flushcache
• If you're running Mac OS X 10.4 Tiger, start Terminal, and then run the following command: lookupd -flushcache

Clear cached data and corrupted certificates in Lync

First, delete the following folders:

Sign In Microsoft Email

• Users/Home Folder/Library/Caches/com.microsoft.Lync
• Users/Home Folder/Documents/Microsoft User Data/Microsoft Lync History

Then, delete any corrupted or cached certificates. To do this, follow these steps:

1. Open the Keychain Access certificate management utility. To do this, in Finder, click Applications, click Utilities, and then click Keychain Access. Or, search for Keychain Access by using Spotlight.

2. In the left pane, click login, and then click Certificates.

3. In the right pane, find a certificate that's named Unknown or Communications Server, select it, and then delete it.

   Note You may have to unlock your keychain by using your password.

4. Close Keychain Access.

5. Restart Lync for Mac.

Important

Before you perform the next step, try reproduce the issue by using a new test user account. If the issue doesn't repeat in the new account, then follow these steps:

1. Open Keychain Access Preferences, and then click Reset My Default Keychain.

2. Open Finder, locate the following folders, and then delete them:

   /Users/Home Folder/Documents/Microsoft User Data/Microsoft Lync Data

   /Users/Home Folder/Documents/Microsoft User Data/Microsoft Lync History

Federated users synchronized from on-premises Active Directory Domain Services can't sign in by using a password that's longer than 16 characters

Organizations that have on-premises customer password policies may allow for passwords to exceed 16 characters. By default, the password policy in Office 365 restricts passwords to 16 characters or less. Because of the Windows Challenge/Response (NTLM) authentication mechanism in the Mac OS, passwords that are longer than 16 characters aren't recognized correctly, and this causes sign-in to fail.

To work around this issue, the user should change his or her password to be 16 characters or less.

Lync for Mac crashes and the user receives an EXC_BAD_ACCESS error

This error message usually occurs when Lync for Mac tries to integrate or schedule meetings with an Exchange mailbox that isn't hosted in Exchange Online. This scenario isn't supported in Skype for Business Online. For the best experience, you should use both Skype for Business Online and Exchange Online. However, if that isn't an option, follow these steps as a potential workaround:

1. Open Finder, locate the following folder, and then delete it:

   DocumentsMicrosoft User DataMicrosoft Lync Data

2. Start Lync for Mac, and then sign in to Skype for Business Online.

3. On the Lync for Mac menu, click Preferences, click Account, and then clear the Use Microsoft Exchange for managing personal information check box.

   Note You must perform step 3 quickly after you sign in.

Collect log files and system information for Lync for Mac issues

Sign In Outlook

To collect log files and system information for Lync for Mac issues, follow these steps:

1. Verify the version of the operating system that's used.

2. Verify the error message that's returned.

3. Turn on logging for troubleshooting in Lync for Mac. To do this, follow these steps:

   1. On the Lync menu, click Preferences, and then click General.
   2. Under Logging, click to select the Turn on logging for troubleshooting check box.

4. Exit Lync for Mac, and then restart Lync for Mac to create a log file.

5. Reproduce the issue.

6. Turn off logging for troubleshooting. To do this, follow these steps:

   1. On the Lync menu, click Preferences, and then click General.
   2. Under Logging, clear the Turn on logging for troubleshooting check box.

7. Collect the log files for Lync for Mac. To do this, follow these steps:

   1. On the menu bar in Finder, click Go, and then click Go to Folder.

   2. In the Go to the folder box, type the path of the logs folder. For example, type /user//library/logs. Then, click Go.

      Note

      <Useraccountfolder> is usually the same as the user name that the user uses to log on the computer. The user name can also be found next to the House icon at the top of the Finder window.

   3. In the Logs folder, collect the log files.

Uninstall and reinstall Lync for Mac 2011

If the steps in this article don't resolve the issue, try to do a clean uninstallation of Lync for Mac 2011, and then reinstall the application. For more information about how to do a clean uninstallation of Lync for Mac 2011, see How to do a clean uninstallation of Lync for Mac 2011.

Sign In Microsoft Exchange Account

More Information

If you're using third-party virtualization software for the Mac, it can coincide with various performance-related issues including but not limited to slow desktop sharing, unexpected poor media quality, possible sign-in and Exchange integration issues. In order to continue, Microsoft technical support may have to confirm that the issue occurs on a computer where the third-party virtualization software isn’t present.

Third-party information disclaimer

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.

Still need help? Go to Microsoft Community.