Outlook desktop app and webmail aren't receiving new emails

Question

I'm back at work after the Christmas break and the Outlook desktop app on the main PC and on our laptop are showing no emails from the period we were away, and are not receiving new emails. If I try signing in via a browser, I get the message below. I am able to sign in to other Outlook accounts with no problem on the same devices. Does anybody know what I should do?

UTC Date: 2026-01-01T10:41:09.908Z
Client Id: [Moderator note: personal info removed]
Session Id: [Moderator note: personal info removed]
Client Version: 20251212003.10
BootResult: configuration
Back Filled Errors: Unhandled Rejection: Error: 500:undefined|undefined:undefined
err: Microsoft.Exchange.Data.Storage.TenantAccessBlockedException
esrc: StartupData
et: ServerError
estack: Error: 500
    at Object.w [as createStatusErrorMessage] (https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.[Moderator note: personal info removed]  at https://res.public.onecdn.static.microsoft/owamail/hashed-v1/scripts/owa.mailindex.[Moderator note: personal info removed]
st: 500
ehk: X-OWA-Error
efe: LO2P265CA0390
ewsver: [Moderator note: personal info removed] 
emsg: TenantAccessBlockedError

Answer 1

Hi @School of Meditation

Thank you for posting your question in Microsoft Q&A. 

Please note that our forum is a public platform, and we will modify your question to hide your personal information in the description. Kindly ensure that you hide any personal or organizational information the next time you post an error or other details to protect personal data. 

We sincerely apologize for the inconvenience caused to your work. Based on your description, it appears that your account encountered an issue while accessing Outlook Web App (OWA). The TenantAccessBlockedException error typically indicates that your Microsoft 365 tenant has been blocked, which can occur due to misconfiguration or specific policy violations. 

If possible, please ask your administrator to check for Compliance or Policy Violations, review the tenant configuration and ensure there are no access restrictions or compliance issues. Resolve any violations or misconfigurations that may be causing the block. 

To better address your issue, could you provide additional information for the following question: 

Does this behavior affect all your tenant or your account only? 

As your current account cannot receive new mail in Outlook desktop app, could you try using another account to send to the affected account and check if there are any NDR or bounce back? 

I will wait for your reply. If you have any additional concerns, feel free to comment below. I would be more than happy to assist. 

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