Unable to save files in Word, Excel, etc. after possible malware or virus

Hi @Jonathan Doyle

Based on what you've described, don't assume the Word/Excel save issue proves the computer is infected.

The earlier flood of “virus detected” / “unauthorized access detected” messages sounds more like unwanted browser notifications or a scam site that was granted notification permission in Edge. Since they returned after rebooting and reconnecting, check Edge's notification permissions and remove/block any unfamiliar sites that are allowed to send notifications. Also avoid clicking any of those alerts or installing the McAfee/Norton/“Windows Antivirus” software they advertise.

You've already done the right thing by running Microsoft Defender Full and Offline scans.

For the Office problem, since both Word and Excel can't save, first, check whether Windows Security is blocking the write operation.

Open: Windows Security → Virus & threat protection → Ransomware protection → Manage ransomware protection

If Controlled folder access is enabled, check its recent block history to see whether WINWORD.EXE or EXCEL.EXE has been blocked. Don't permanently disable Controlled Folder Access just to make Office work; if it is the cause, verify the executable is the genuine Microsoft Office application before allowing it.

Next, try a very simple isolation test. Open Notepad and save a text file to:

C:\Users<your-user-name>\Documents

and then to the Desktop. If Notepad also cannot save, this points away from Office and more toward Windows folder permissions/security/storage. If Notepad saves normally but both Word and Excel fail, concentrate on Office.

For Word and Excel, test Safe Mode: winword /safe and excel /safe

Create a blank document/workbook and try Save As to a simple local folder such as Documents. Microsoft specifically recommends Safe Mode when troubleshooting Excel save failures because add-ins or startup files can interfere with the save process.

If saving works in Safe Mode, disable the Office/COM add-ins and re-enable them individually until you identify the conflict.

If it still fails in Safe Mode, repair Office next: Settings → Apps → Installed apps → Microsoft 365 → Modify → Quick Repair

If Quick Repair doesn't fix it, run Online Repair. I recommend Online Repair when the lighter repair doesn't resolve an Office installation problem.

One other detail is important here. Excel doesn't simply write directly over the existing workbook. During a save, it creates a temporary file in the destination folder, writes the workbook, removes the original as necessary, and renames the temporary file. Security software, permissions, or another process interfering with that sequence can produce “Document not saved” even though the workbook itself isn't necessarily corrupted.

Before changing anything else, could you post the exact Word “file not found” message (a screenshot would be ideal), and let us know:

• whether Notepad can save to the same folder;
• whether Word/Excel can save in Safe Mode;
• whether Controlled Folder Access is enabled; and
• whether the affected paths are local folders or OneDrive folders.

Those results should tell us whether we're dealing with an Office issue, a Windows folder/security issue, or something interfering with file writes.

References:

Troubleshoot Excel save errors

Repair an Office application

Troubleshoot Office using Safe Mode

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