Hi @Jim Robinson PE ,
Welcome to Q&A forum!
Is there a way to use 2019 Excel without OneDrive file conversions to work with earlier Office Excel versions?
< How did you use the OneDrive file conversion?
Usually, we open earlier versions of Excel files and work in compatibility mode.
For more information, please refer to: Use Excel with earlier versions of Excel.
coping 2019 Excel files onto USB drives and Internal NAS (Synology family) result in the problem.
< Since we do not have a similar test environment, I cannot test further. Thanks for your understanding.
Any misunderstandings and updates, pelase let me know.
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