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Please try Copilot in:
- A new blank document
- The same document in https://word.cloud.microsoft/
- Another Microsoft 365 app, if Copilot is available there
If Copilot works in a blank document or in the web version, the issue is likely limited to that document or the desktop Word installation. If it keeps spinning everywhere, run the Copilot connectivity troubleshooter from the Windows Get Help app. Microsoft states that it checks for firewall rules and other connection blockers. Microsoft Copilot troubleshooters.
Also let us know the operating system, Word version, account type, and whether every document is affected.