I'm trying to convert the old classic window info to my current existing 365 mailbox.

To add mailboxes from classic Outlook to your existing Microsoft 365 account, you may need to create a new Outlook profile or ensure that your account settings are correct. Here are some steps you can follow:

1. Check Account Compatibility:
   • Ensure that the accounts you are trying to add are supported in the new Outlook. The new Outlook supports Microsoft 365 work and school accounts, Outlook.com, Gmail, Yahoo, iCloud, and other accounts connecting via IMAP and POP.
   • On-premises Exchange accounts are not supported in the new Outlook.
2. Troubleshoot Connection Issues:
   • If you encounter issues connecting, consider using the ExcludeLastKnownGoodUrl registry setting to prevent Outlook from using the last known good AutoDiscover URL. You can set this in the registry under HKEY_CURRENT_USER\Software\Microsoft\Office\<x.0>\Outlook\Autodiscover with a value of 1.
3. Check for Updates:
   • Ensure that you are using the latest version of Outlook, as older versions may not support the features necessary for connecting to Microsoft 365.

If you continue to have issues, consider reaching out to Microsoft Support for further assistance, especially if the problem persists across different applications like Word.

References:

• Outlook doesn't connect or web services don't work after migration to Microsoft 365
• Supported accounts in new Outlook for Windows

Hi @Karen Smith

Thank you for posting your question in the Q&A Forum. 

The difficulties you’re seeing with both Outlook and Word usually happen because the apps are still signed in with old accounts or there’s a profile conflict when moving to Microsoft 365. Here is the recommended approach to resolve them: 

1. Create a New Outlook Profile

Since your current setup isn’t recognizing your Microsoft 365 account, creating a new Outlook profile is the most reliable way to connect properly. 

• Open Control Panel on Windows. 
• Search for and open Mail (Microsoft Outlook) > Show Profiles... > Add.... 
• Create a new profile and sign in with your Microsoft 365 email and password. 
• Set this new profile as the default and launch Outlook. Your mailbox should now synchronize correctly. 

If you do not see all your old emails after setting up the new profile, you may need to export your existing data from the classic Outlook to a PST file and import it into the new profile. 

You can follow Microsoft’s official guide here: Import email, contacts, and calendar from an Outlook .pst file - Microsoft Support 

2. Sign In to Word with Microsoft 365 Account

If Word isn’t letting you open saved documents, it’s usually because it’s not signed in with your current Microsoft 365 account. 

• Open Word and go to File > Account. 
• Sign Out of any old accounts that may be listed. 
• Click Sign In and use your Microsoft 365 email and password. 

Once signed in, you will have full access to your license. You can then move any older documents to your OneDrive folder for cloud backup and future accessibility. 

Please try these steps starting with the new Outlook profile creation. Let me know your results or if you encounter any specific error messages, and I’ll be happy to assist further. 

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