These instructions are for Outlook web mail, although they will be somewhat similar to the desktop versions on Windows and MacOS. In most cases, adding or removing an add-in in one place will do so in all versions of Outlook that you utilize. However, you may need to add/remove in multiple places if this does not work for you.
To add (or remove) the Salesforce Outlook Add-in, Navigate to "Get add-ins". The easiest way to do this in Outlook web mail is to simply open a new message, and use the edit ribbon at the bottom of the message.
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Next, click admin-managed, and choose to add (or remove) Salesforce. If you are removing the add-in, you can stop here.
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Click this to open the plug-in and sign in.
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Select "Production" and then "Log in to Salesforce".
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If prompted, allow Salesforce to open a new window.
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Select, "Use Custom Domain".
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Enter our productions org's custom domain "darden" and click "Continue".
To add (or remove) the Salesforce Outlook Add-in, Navigate to "Get add-ins". The easiest way to do this in Outlook web mail is to simply open a new message, and use the edit ribbon at the bottom of the message.
Click this to open the plug-in and sign in.