Suddenly can't open some documents, problems with others

Hi, Naomi Hurley-Rayburg

Since several documents started failing at about the same time, this may be an account authorization, security-policy, or background software issue rather than damage to each individual file.

Besides the solutions provided by the Q&A Assist, here are some suggestions you can try:

Open the affected document directly in Word for the web. If it opens there, confirm that the desktop app is signed in with the same Microsoft account that owns or has permission to the file. Restricted documents can fail when Office is using the wrong account or an older version that does not support the applied protection.

If the file came from email or was downloaded, right-click it in File Explorer, select Properties, select Unblock if shown, then choose Apply. Only do this when you trust the file. Files from potentially unsafe locations can be restricted by Protected View or File Block settings.

Temporarily pause third-party antivirus, backup, or encryption software, then test one document. It is recommended that the Office file-cache folder be excluded from that software’s scanning or backup jobs, since these programs can temporarily lock files or interfere with Office uploads.

If this affects work or school files, ask the SharePoint owner to verify that your permission or sensitivity-label access has not recently changed.

Thank you for your patience in reading, I hope this information has been helpful to you. 

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