/o=exchangelabs/ou=exchange administrative group (fydibohf23spdlt)

Hi, CarolPullen

Welcome to Microsoft Community.

I realize that you've encountered a problem when sending emails with your email account on Classic Outlook for Windows.

According to your description, everything works well with the same account on Outlook.com. And you have contacted our agency while it still does not work.

According to the NDR you provide, it clearly shows that "This message could not be sent. You do not have the permission to send the message on behalf of the specified user. "

Some users are experiencing the same problem as you, trying to configure a new Outlook profile doesn't work, please follow the advice below until you have investigated further to find a fix for this issue:

• Please try starting Outlook in Safe Mode to see if you can send emails. Hold down the Ctrl key and double click on the Outlook icon to select Safe Mode Startup.
• If Safe Mode startup does not work, please try creating a new Windows local user on your wife's laptop, which you can do by going to Lock Screen > Other Users and try to configure your wife's personal account to Outlook to see if you can send emails.
• Alternatively. as a workaround. you can also add the connected account as an Outlook.com secondary alias. To perform this action:
  • Go to this page https://account.live.com/names/Manage.
  • Under Account Aliases, click Add Email. Under Add Alias, click the Add an existing e-mail address as a Microsoft account alias radio button.
  • Click the Add Alias button.

Thank you for your cooperation and please feel free to share with me on any developments about this issue!

Best Regards,

Cece | Microsoft Community Support Specialist

My problem actually started after wiping my drive and starting afresh. I left a company who said I could keep the computer. I was wondering if this problem was not due to software on their side. Did anyone on this group experience this problem after leaving a company that had MS Exchange and then switched to a personal MS Exchange?

I am now using the web version only…which is not as good as the classic online version. This is the only way I can use outlook.

I have actually gone as far as wiping my laptop which has the issue. This still didn’t solve the issue.

All my other devices including other laptops and pc are absolutely fine. I am come to the conclusion that Microsoft has somehow blacklisted my actual device from sending emails using that email address and there is nothing I can do from my end.

I cannot believe the level of support. Absolutely zero!

I am currently having the same issue that just started in the last 24 hours. I have done all the various troubleshooting recommended and still trying to resolve issue as the Admin using the Outlook Classic since the New Outlook is void of several important features.

IF you setup a new outlook profile it will work.. but only if you DO NOT ADD MULTIPLE EMAIL ACCOUNTS ... after hours of testing it appears that there is an issue with Outlook Classic now if you have more than one email account attached. At some point it breakdown. I am guessing other users have more than one email account which is where MS Support should look to fix this bug.

I, and many users, are having this exact issue.

A WORKAROUND does not solve the problem and we should not have to be using another alias!.

I found a similar issue dating back to 2019 and Microsoft were still 'investigating'.

This is not good enough