URGENT: Multiple Copilot Projects and Project Chats Missing After New Copilot Migration / Sync Issue

Do not delete chats, reinstall apps, unlink accounts, or clear Copilot data; immediately report the missing migration in Copilot and open a Microsoft support case, because Microsoft documents no user-controlled forced resynchronization or self-service restore.

Immediate, non-destructive actions

1. Check for a migration-access message
   • Open the updated Copilot app.
   • Look for a message such as “coming soon”, migration still in progress, or a link to previous chats/content.
   • Use that link if shown. Microsoft says eligible content can remain accessible through such a link while migration continues.^1^
2. Conditionally test whether the original account still has Legacy access This applies if there is any possibility that Legacy Copilot used another personal Microsoft, Google, or Apple account/sign-in method:
   • Open a new private/InPrivate browser window.
   • Go to copilot.microsoft.com.
   • Sign in with each original personal account using the original method—for example, Continue with Google rather than manually entering the same email another way.
   • If the browser remains on copilot.microsoft.com, that account has not migrated yet and Legacy Copilot can still be used there.
   • If redirected to copilot.com, that account has migrated or is completing migration.^1^
   If content appears, copy the critical legal material immediately into local documents and OneDrive. Do not alter or delete the original chats.
3. Report the migration failure from Copilot
   • Select … in the upper-right corner.
   • Select Send feedback → Report a problem.
   • Include:
     • Approximate date, time, and time zone when Legacy access disappeared.
     • “Legacy Projects renamed to Notebooks, but the Notebooks and associated chats are missing.”
     • Account type and original sign-in method.
     • Device, operating system, and Copilot app/browser versions.
     • Titles or approximate creation dates of missing Projects.
     • Screenshots with legal, personal, and confidential details removed.
   This report supplies session information needed for investigation.^1^
4. Open a support case now For a personal account, open the Windows Get Help app, describe the issue as “Copilot Legacy migration missing Projects/Notebooks and chat history,” then select Contact Support when offered. Depending on availability, Microsoft may offer browser chat or a callback.^2^

What Microsoft’s guidance establishes

• Projects were renamed to Notebooks. Existing eligible Projects are expected to move and appear under Notebooks.^1^
• Chats and most other eligible content migrate automatically, but migration can take time and temporary functionality gaps can occur during rollout.^3^
• Missing from the interface does not prove deletion, but public documentation cannot confirm whether a particular user’s missing data still exists. Microsoft Support must investigate the account’s migration state.
• There is no documented force-resync or self-service restoration control. Repeatedly reinstalling, deleting data, or changing linked accounts is therefore not a supported recovery method.
• Important exception: Group Chat threads and their content did not carry forward after August 18, 2026. Content created through retired features, including Group Chat, Podcasts, and Deep Research, is handled differently.^3^
• Files shared or generated in standalone Copilot are moved to OneDrive, so inspect OneDrive for generated documents even if their chats are not visible.^3^

If this was a work or school account

Contact the Microsoft 365 administrator immediately. Work and personal accounts remain separate, so content does not flow between them.^3^

Ask the administrator to:

1. Open a service request through Microsoft 365 admin center → Help & Support.
2. Preserve relevant data under the organization’s retention and legal-hold procedures.
3. Have an authorized compliance administrator search Copilot interaction data through Microsoft Purview Content Search/eDiscovery. Microsoft documents that work-account prompts and responses are stored as Copilot activity history and can be searched by authorized administrators.^4^

Because the material concerns pending litigation, preserve screenshots, support request numbers, dates, and exported copies without editing the originals. Also remove the personal name from the public Q&A post.

References

1. Troubleshoot Your Content in the Updated Copilot App | Microsoft Support
2. Get Help for Microsoft personal account users | Microsoft Support
3. Copilot App Updates for Personal, Work, and School Accounts | Microsoft Support
4. Data, Privacy, and Security for Microsoft Copilot