Fix Microsoft 365 email not working

Here are some issues you might see when using Microsoft 365 email and ways to solve them.

If	Do this
You can’t open Outlook.	Diagnose your error message to fix.
You’re having trouble signing in.	Try one of these options.
You can’t send or deliver email and get an error message.	Find your error and its resolution.
You’re not receiving email.	Try these solutions to get incoming email.
You can’t set up Microsoft 365 on your iOS device.	Check these verification errors.
You can’t use autodiscover or setup wizards.	Try manually setting up Outlook. This won’t work with Office 2016, or if you’re using a Mac.
You’re missing email after moving from Workspace Email to Microsoft 365.	Follow these troubleshooting steps.
You can’t send email on Windows 10.	See this solution from Microsoft.

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