ACCESS DENIED

Access denied errors when signing in to Outlook or Outlook on the web usually mean the account or mailbox is blocked or missing required permissions. The exact fix depends on who manages the account.

For a work or school (Microsoft 365) account using Outlook on the web (OWA):

1. If the error looks like a 403 “Sorry! Access denied” page, the cause can be missing permissions on the mailbox.
2. An administrator must:
   • Sign in to the Microsoft 365 admin center.
   • Open the Exchange admin center.
   • Go to permissions → user roles.
   • Open Default Role Assignment Policy.
   • Under Other roles, ensure MyBaseOptions is checked, then save.
3. If the mailbox itself is disabled (common when seeing OWA startup errors), the tenant administrator must:
   • Check the mailbox status in Exchange Online (for example, verify AccountDisabled is not True).
   • Re‑enable the mailbox if it is disabled.
4. After changes, sign out of all sessions, clear browser cache, and try again (or use InPrivate/Incognito mode) to rule out browser issues.
5. If this is a corporate/organizational account, contact the organization’s IT or Microsoft 365 admin, as only they can adjust these settings or re‑enable a disabled mailbox.

For Outlook mobile (Android/iOS):

• If the sign‑in fails with an “Access Denied” login error, the account may be blocked from using Outlook mobile by policy. Only the IT administrator can unblock or allow the account for Outlook mobile. Contact the organization’s IT admin for details.

If the account is a personal Outlook.com/Hotmail account and access is denied:

• The account may be locked or blocked due to too many failed sign‑in attempts or suspicious activity. In that case, use the standard Microsoft account recovery and unblock flows (password reset, account recovery form, or unblock process) as described in the Outlook.com account lock and recovery guidance in the references.
• If recovery attempts hit rate limits, wait at least 24 hours without further attempts before trying again.

If none of the above applies or the account belongs to an organization, the next step is always to contact the account’s administrator or support team, since only they can see whether the mailbox is disabled or the account is blocked by policy.

References:

• 403 Sorry Access denied error when a user tries to sign in to Outlook Web App in Microsoft 365
• Access Denied: Login Error
• Not able to have access to my email ! - Microsoft Q&A
• Why can't I log in to my Outlook account? - Microsoft Q&A
• Locked out of my Outlook account and recovery options not working - Microsoft Q&A
• Can't sign in to my email - Microsoft Q&A
• Unable to change password in my Outlook - Microsoft Q&A