Important:
This feature is no longer being sold by Wix.
If you purchased a Microsoft Office 365 mailbox through Wix, you can easily access and manage it from within your Wix account.
To access your mailbox:
Go to Business Email in your Wix account.
Click Go to Inbox next to the relevant mailbox.
Enter your mailbox credentials and click Sign in.
This article is credited to the Wix team - https://support.wix.com/ and we thank them for that!