How to suppress the AutoDiscover Redirect warning in Outlook for Mac

How to suppress the AutoDiscover Redirect warning in Outlook for Mac

When you use Outlook on Mac with Office 365, you may receive a prompt saying: Outlook has been redirected to the autodiscover-s.outlook.com server to get the new settings for your account. Do you want to allow this server to configure your settings? In this article, I will show you how to disable or enable automatic detection for Outlook on Mac with Office 365.

Outlook has been redirected to the autodiscover-s.outlook.com server to get the new settings for your account.

The displayed URL is https://autodiscover-s.outlook.com/autodiscover/autodiscover.xml. You should click on To allow only if you trust the source of your exchange or if the administrator asks you.

You can check the box and click Allow or Deny. If you do not check this box, you will be prompted each time you launch Outlook.

How to remove AutoDiscover Redirect warning in Outlook for Mac

When Microsoft Outlook 2016 for Mac connects to an Office 365 account, Autodiscover is redirected from HTTP to HTTPS. It is there that you receive the warning message. If you choose to allow and trust the source, you will no longer be asked to do so.

Disable or enable automatic discovery for Outlook on Mac with Office 365

Assuming you do not want to, and your administrator also suggests not doing so, here's how you can disable automatic detection for Outlook on Mac. Follow the steps:

  • Quit Outlook when it is running.
  • Press Command + Spacebar and type Terminal.
  • When it appears in the search, select it with the help of the down arrow and open it.
  • Enter the following command in the Terminal window, and press Enter.
defaults write com.microsoft.Outlook TrustO365AutodiscoverRedirect -bool true

If you want to disable, use false instead.

the TrustO365AutodiscoverRedirect preference can be configured to use the following values:

Parameter values Details
true Do not request approved Office 365 endpoints. Outlook defines which URLs are approved, which is not configurable.
false Outlook will use the default behavior, which is to prompt when automatic discovery redirects occur.
if the value is not present Outlook will use the default behavior, which is to prompt when automatic discovery redirects occur.

If you publish this, you will not receive any message about permission and trust in the URL source for your Outlook on Mac.

I hope it helps!

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