What should I do if I encounter the error "this excel file format is different than file extension" when opening an Excel file on a network share?
Applicable Products:
All NAS series
Root Cause
You may encounter this issue when trying to open Excel files via an SMB connection to the NAS. This is a known issue caused by security update for Excel 2013 (KB5002242).
Solution
Install update for Excel 2013 (KB5002268).
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