Fixing an account with 3 emails sharing all folders

Question

When I access account settings in Outlook 2019 Classic, I see 3 email addresses which is correct. There is my primary, another that is set up to function with the primary and a 3rd that I want but cannot add to the primary. How is this done?

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Moved from Microsoft 365 and Office | Other

Answer 1

Hi Bruce W. Wille,

From your description, this behavior typically comes down to the difference between a separate account and an alias.

In Classic Outlook for Windows, Outlook treats an account and an alias very differently:

• An account is a separate mailbox with its own sign‑in.
• An alias is an additional email address that uses the same Microsoft account sign‑in and the same mailbox.

Because of this, if the third address is meant to work under the same Outlook.com / Hotmail / Live account as the primary address, it must be set up as an alias on the Microsoft account. This cannot be configured from within Outlook itself.

If the third address is intended to be its own mailbox, it should be added in File > Add Account.

To make sure the guidance matches your goal, could you clarify:

• Is the third address an Outlook.com, Hotmail, or Live address?
• Do you want it as a separate mailbox, or as an alias of the primary account?
• What happens when you try to add it in Outlook?

Please let me know if this proves useful to you, or if you would like further assistance.

I'm looking forward to your reply.

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Answer 2

Need clearer info.

Answer 3

Outlook shows three separate email accounts because they are three different Microsoft accounts or mailboxes. Making them “share all folders” under one primary the way described requires that the additional addresses be aliases on the same Microsoft account, not separate accounts.

If the third address is already its own Microsoft account (its own mailbox), it cannot be merged into the primary account or added as an alias to that primary. Microsoft does not support merging accounts or moving an existing Outlook.com address between Microsoft accounts.

The only supported options are:

1. Use it as a separate account in Outlook
   • Keep the third address configured as its own account in Outlook 2019 (as it is now). It will always have its own mailbox and folders.
2. Use aliases on a single Microsoft account (if the address is not already a Microsoft account)
   • For addresses that are not already tied to a different Microsoft account, they can be added as aliases to the primary account and share the same mailbox/folders.
   • Aliases share the same inbox, contacts, and settings; the primary alias is what appears on devices.
3. If the third address is already a Microsoft account
   • It cannot be added as an alias to the primary account.
   • Microsoft does not allow account merging or recycling of existing Outlook.com aliases into another account.

So if the third email address is already its own Outlook.com/Microsoft account, there is no supported way to make it “function with the primary” and share all folders; it must remain a separate account in Outlook.

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References:

• Which account do you want to use?
• How to add an existing outlook.com account to my existing microsoft account? - Microsoft Q&A
• I realize I have 2 different accounts. How do I combine the 2? - Microsoft Q&A