Outlook is using a temporary email and I cannot receive emails

Step 1 – Close Outlook

Close Outlook completely.

In Task Manager, make sure there are no Outlook.exe or MSOSYNC.exe processes still running. End them if there are.

Step 2 – Add the registry flag to stop Outlook talking to Microsoft 365

Set the ExcludeExplicitO365Endpoint flag under Outlook’s AutoDiscover key.

1. Press Start, type PowerShell.
2. Right-click Windows PowerShell → Run as administrator (or at least run it as the same Windows user who uses Outlook).
3. In the blue PowerShell window, paste the following and press Enter:

# Make sure the AutoDiscover key exists
New-Item -Path "HKCU:\Software\Microsoft\Office\16.0\Outlook\AutoDiscover" -Force | Out-Null

# Tell Outlook to exclude the Office 365 endpoint
Set-ItemProperty -Path "HKCU:\Software\Microsoft\Office\16.0\Outlook\AutoDiscover" `
    -Name 'ExcludeExplicitO365Endpoint' -Value 1 -Type DWORD -Force

4.You shouldn’t see any errors; it will just return to the prompt. Close PowerShell.

Step 3 – Restart the PC

Step 4 – Create a fresh Outlook profile to your hosted Exchange

After the reboot:

Open Control Panel → Mail → Show Profiles….

Remove the old problem profile(s) (the ones that were using the temporary mailbox).

1. Click Add…, name it something like "New".
2. Enter:
   • Your Name: Your Name
   • Email Address: ******@domain.com
   Password: your Exchange password
3. Let the automatic setup run. With the new registry flag in place, Outlook should now ignore Microsoft 365 and use your hosted exchange environment instead.

If it finishes without the “name cannot be matched” error:

Start Outlook using this new profile.

• Go to File → Account Settings → Account Settings… and check:
  • Only your ******@domain.com Exchange account is listed, and
  It’s set as Default, with no odd Outlook.com accounts.

You should then see your full mailbox and be able to send/receive as ******@domain.com again.

Hi @Tim Clark

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. 

As my research, looks like the issue “Your mailbox has been temporarily moved on Microsoft Exchange server” might relate to your Outlook profile or local cache (OST file) is corrupted, causing Outlook to create a temporary mailbox instead of connecting to your real Exchange account.

Note: Do not choose to connect to the temporary mailbox. This may cause data loss. 

You could try to follow these workarounds: 

Remove All Extra Outlook Profiles (Keep Primary Profile) 

Exit Outlook completely. 

Open Control Panel > Mail 

To find Mail: In Control Panel’s search box, type Mail. 

Click Show Profiles. 

Select any profile you want to remove and click Remove. 

You’ll see this warning:  “Careful, if you remove this profile, offline cached contents for its accounts will be deleted. Learn how to make a backup of the offline .ost files for the accounts.” 

Back up your .ost files before proceeding. 

Click Yes to confirm removal. 

Repeat these steps for all profiles except the user’s primary profile. 

Click OK to close the Mail dialog box. 

Restart Outlook and check if the issue is resolved. 

If that doesn't resolve the issue, you could consider create a new Outlook Profile and Remove the Original. 

Exit Outlook. 

Open Control Panel > Mail. 

Click Show Profiles, then click Add. 

Enter a name for the new profile and click OK. 

Complete the Add Account wizard to add the user’s email account. 

Click Finish. 

Back in the Mail dialog box, select the original profile and click Remove. 

Same warning appears:  “Careful, if you remove this profile, offline cached contents for its accounts will be deleted…” 

Back up .ost files, then click Yes. 

Under Always use this profile, select the new profile you created. 

Click OK and restart Outlook. 

These solutions help remove corrupted profiles and create a fresh one, which forces Outlook to rebuild its connection to the Exchange server.

This process resolves temporary mailbox issues and restores proper sending and receiving functionality with the correct business email address. 

You can refer via: "Your mailbox has been temporarily moved on Microsoft Exchange server” message when an Office 365 u… 

Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution. 

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