How to fix Outlook Error 500

Recently I was reported an error message which occured when a user tried to access Outlook on the Web (Outlook WebApp). User was unable to access the emails via Outlook on the web but can access emails using Outlook desktop client.

There could be many reasons which results in 500 error code. You could be getting one of the error message. Let’s check the Error types. These Errors will occur irrespective of the which Internet browser you are using.

  • Outlook on the Web Error 500 – Repeating redirects detected.
  • Outlook on the Web Error 500 – We Couldn’t find a mailbox for this account.

Solution 1 – Repeating redirects detected

Let’s check the steps on how you can fix Repeating redirects detected Error message for Outlook on the web.

Error 500 – Something went wrong
Repeating redirects detected. Click here to sign out.
Outlook Error 500 Repeating redirects detected

Repeating redirects detected Issue occurs when a user tried to access Outlook on the Web. This issue is not an organization wide issue and can be related to one user or few users. Mostly this issue is common for users with Admin roles assigned.

Users are assigned admin roles depending upon the department they are working for. For example, If a user is managing email infrastructure then they would be assigned Exchange administrator role. If a user is managing sharepoint environment, then a user would be assigned sharepoint administrator role and so on.

But a user can have multiple admin roles for example: A user can be Exchange administrator, PowerBI administrator, Security Administrator, sharepoint administrator, teams administrator, Helpdesk administrator, User Administrator etc.

You may get Outlook Error 500 – Repeating redirected detected error when a user is assigned with too many administrator roles on Microsoft 365 admin center. The cause of this issue is not known yet but it could be a bug in the system on which Microsoft team might be working on it.

To Fix this issue, you simply need to login on Microsoft 365 admin center as Global administrator and uncheck the roles for the user which are not required. Second step will be to ask the user to Sign out everywhere from Microsoft 365. User does not need to Sign-out from each device manually, we will use an option which will do this automatically for the user using just one click.

  • Login on Microsoft 365 admin center using Global admin rights.
  • Go to Users > Active Users > Select the user who reported this issue.
Too many admin roles
  • On the right hand side pane, Select Manage roles under Roles.
Manage roles Microsoft 365 admin
  • Uncheck the admin roles which are not needed. Only keep the one’s which user requires. For the example user Jatin Makhija, as we know he is an Exchange admin, we have only selected Exchange Administrator role and removed all other admin roles.
  • Click on Save changes button to complete this change.
uncheck roles from M365 admin center

Sign out from everywhere

Next step may or may not be needed. But its a best practice while testing to make sure that the access to Outlook is fine and issue is 100% resolved. User can log out from Outlook from each device manually but you could choose the shortcut and click on Sign out everywhere link instead to speed up the process.

Sign out from everywhere office 365
  • Click on Ok on Sign out everywhere pop-up.
Sign  out everywhere

After sign out, you can wait for couple of minutes and try again, Hopefully this error should be resolved for you.

Solution 2 – We Couldn’t find a mailbox for this account

Let’s check the steps for the Outlook Error 500 – Something went Wrong. We couldn’t find a mailbox for this account.

Error 500 – Something went wrong
We Couldn’t find a mailbox for this account. Either they don’t have a mailbox or don’t have a license assigned. To fix it, contact your Email Admins and ask them to assign a valid license to your account using M365 Admin Portal per instructions.
Outlook Error 500 We Couldn't find a mailbox for this account

This error usually occurs when there is no mailbox associated with the account you are trying to login or Exchange online license has not been assigned or removed from the user account from Microsoft 365 admin center.

I had a weird one where a Exchange Online License was assigned to the user but there was no mailbox created when checked from Microsoft Exchange admin center. In that case, you can remove Exchange online license from the user and re-add it to see if a mailbox gets created.

If its still having issues then you could use a powershell command Get-MsolUser -HasErrorsOnly to find if there are any errors related to the user account.

Make sure the user is having a mailbox associated with it and Exchange Online license has been assigned. To check these, please follow below steps:

  • Login on Microsoft 365 admin center using Global admin rights.
  • Go to Users > Active Users > Select the user who reported this issue.
  • Click on License and apps tab.
  • Make sure License has been assigned to the user and if a License is assigned then make sure Exchange Online Plan 1 or Plan 2 is also checked.
Exchange Online plan 2 outlook error 500

Other Solutions

Hopefully you should be able to resolve Outlook Error 500 with the solutions provided in previous sections of this blog post. However, if the above solutions does not fix Outlook Error 500 then you can also try below solutions.

First you can try to access Outlook on the web using Incognito mode of the browser or In-Private Mode of the browser. If you are able to successfully login to Outlook then it means that browser cache is causing issues.

Clear your browser cache and cookie information. Whichever browser you are using, you can go to browser Settings and search for Cookie and then clear cookies and browser cache from there.

Check Service Health in Microsoft 365 admin center

You should regularly monitor the Service health in Microsoft 365 admin center. Particularly if most of the users in your organization are facing the same issue. If there are any issues with exchange online services, you would be able to find some information from there.

To check the Service health, you can follow below steps:

In this area, you can check the service Exchange Online to see if there are any incidents or advisories given which could suggest that this error is due to service health issue.

Exchange Online service health


In this blog post, we have seen different troubleshooting options which could help us resolve the error 500 when trying to access Outlook on the Web. Hopefully one of the solution will work for you and resolve this error permanently. Make sure to regularly monitor Exchange online service health which could save a lot of time for administrators.

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