The email cannot be used

Question

UTC Date: 2025-11-20T17:53:34.295Z
Client Id: **PII Removed**
Session Id: **PII Removed**
Client Version: 20251031008.37
BootResult: configuration
Back Filled Errors: Unhandled Rejection: Error: 500:undefined|undefined:undefined
err: Microsoft.Exchange.Clients.Owa2.Server.Core.OwaUserHasNoMailboxAndNoLicenseAssignedException
esrc: StartupData
et: ServerError
estack: Error: 500
    at Object.w [as createStatusErrorMessage] (https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.f6526c96.js:2:8742)
    at https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.f6526c96.js:2:41380
st: 500
ehk: X-OWA-Error
efe: TP0P295CA0039
emsg: UserHasNoMailboxAndNoLicenseAssignedError

Answer 1

The error message you are encountering indicates that the user does not have a mailbox and no license assigned. This typically happens when the user's account is not properly set up in the Microsoft Exchange environment. To resolve this issue, you should ensure that the user has a valid mailbox and that a proper license is assigned to their account.

Here are a few steps you can take:

1. Verify that the user account exists in Active Directory and is enabled.
2. Check if the user has been assigned a valid Exchange Online license.
3. If the user is part of a protected group, consider creating a separate account for email purposes, as using accounts from protected groups for email can lead to issues.

If the problem persists, you may need to contact your IT administrator or Microsoft support for further assistance.

Answer 2

Hi @Matt Feng,

Welcome to Microsoft Q&A Forum.

Based on the logs you provided, the error is: Microsoft.Exchange.Clients.Owa2.Server.Core.OwaUserHasNoMailboxAndNoLicenseAssignedException   Error 500: UserHasNoMailboxAndNoLicenseAssignedError

This error typically occurs when the account does not have an Exchange Online mailbox assigned or the account is missing the required Microsoft 365 license that includes Exchange Online services. Without a mailbox and proper licensing, Outlook on the web cannot load your mailbox data, which results in this error.

This issue requires administrative action and cannot be fixed by an end user. Please contact your IT administrator and ask them to:

•  Ensure your account has a valid Microsoft 365 license that includes Exchange Online (e.g., Microsoft 365 Business Standard, E3, or E5).
• In the Microsoft 365 Admin Center, navigate to Users → Active Users → [Your Account] → Licenses and Apps and check that Exchange Online is enabled.
• If not, assign the appropriate license, they can also unassign and reassign the license to reactivated it.
• The reactivated process may take up to 24 hours to finalize.

Then I'd suggest the admin verify your mailbox existence by using PowerShell:

 

Get-Mailbox -Identity ******@domain.com

If no mailbox exists, create one:

New-Mailbox -UserPrincipalName ******@domain.com -FirstName 'First' -LastName 'Last'

 

Please try to open Outlook via Outlook Web Access (OWA) in an incognito mode to see if you're able to use it after ensuring the mailbox and license are correctly configured.

 

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this. 

Thank you for your patience and your understanding. If you have any questions, please feel free to reach out. 

I'm looking forward to your reply

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