Outlook 2016 for Mac crashes when a Proxy Auto Configuration file is used


Consider the following scenario:

  • You use Microsoft Outlook 2016 for Mac on a Mac computer that's configured to use a Proxy Auto Configuration (PAC) file.
  • You try to access a remote resource by using the HTTP protocol.

In this scenario, Outlook 2016 for Mac crashes.


This issue occurs when a file-based PAC file is used in the Automatic Proxy Configuration setting in Mac operating system.


A file-based PAC file is a file whose URL begins with file://.


To resolve this problem, host the PAC file on a web server that can be accessed by using the HTTP protocol, and then specify the URL of the file in the Automatic Proxy Configuration setting of the Advanced Network preferences in Mac operating system.

To edit the Automatic Proxy Configuration settings in Mac operating system, follow these steps:

  1. Open System Preferences.
  2. Select Network.
  3. Select Advanced.
  4. Select the Proxies tab.
  5. Under Select a protocol to configure, select Automatic Proxy Configuration.
  6. Enter the URL of the hosted PAC file.

More information

  • Talk to support

    To report issues or provide feedback, go to Help > Contact Support in Outlook for Mac.

  • Ask the community

    Get help from experts in the Microsoft 365 and Office.

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