Hello Ross Young,
Thank you for reaching out in Microsoft Q&A forum
I understand how confusing this is, especially since you can sign in to your Microsoft account normally but are blocked only when opening the shared Excel link with a message saying the account is locked.
From the screenshot, the message “Your account has been locked. Contact your support person to unlock it” indicates that the account is being flagged at the service level used to access shared files (such as OneDrive or SharePoint), even though standard sign-in still works.
Here are the recommended steps to resolve this:
- Try unlocking your Microsoft account by signing in at https://account.microsoft.com and follow any security verification prompts shown there.
- If you do not see an option to unlock the account, reset your password and then wait a short period before retrying the shared document link in a new browser session.
- Open the shared Excel file using an InPrivate/Incognito browser window to ensure cached credentials are not interfering.
- If the problem continues, contact Microsoft Support directly select Microsoft account > Sign‑in issues > Account locked, then choose Contact Support and follow the on‑screen steps to submit your request.
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