Last Updated: September 8, 2022

ISSUE

After installing Office 2013 security update KB5002242, you get the following warning when opening Excel files from a network location when the file extension is correct: 

The file format and extension of %FILENAME% don't match. The file could be corrupted or unsafe. Unless you trust its source, don't open it. Do you want to open it anyway?

STATUS: FIXED

The issue was fixed in update for Excel 2013 KB5002268, released on Tuesday, September 6, 2022.

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See Also

Fixes or workarounds for recent issues in Excel for PC

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