Inaccessible chat after Copilot updat.

Welcome Ahmad Ghaderi-Panah,

I understand how concerning it can be when a Copilot conversation becomes inaccessible after an update.

Before troubleshooting further, could you please confirm:

• Are you signed in with a personal Microsoft account or a work/school account?
• Is the missing chat unavailable in both the Copilot app and on Copilot on the web?
• Do you see the rest of your chat history, or is only this specific conversation missing?

In the meantime, please try these quick checks:

• Open Copilot on the web and make sure the left sidebar is expanded to view your conversation history. Microsoft states that signed-in users can access previous conversations from the conversation history panel. Conversation history in Microsoft Copilot
• Verify that you are signed in with the same Microsoft account that was used to create the chat.
• Open Copilot in an InPrivate/Incognito browser window and check whether the conversation appears there.
• If available, check whether the conversation is visible on another device where you use the same account.

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