HELP!!-somehow yesterday my 2016 .xlsx file extention got changed to .xlsb - won't open !!

[ncngrr5]

HELP!!-somehow yesterday my 2016 .xlsx file extension got changed to .xlsb - won't open !!

Help - I have tried renaming the file, I have tried online file tools, file give's me this error:

Excel cannot open file "Swaseys_file.xlsb" because file format or file extension is not valid. Verify that
the file has not been corrupted and that the file extension matches the format.

Can someone fix the file for me?

Thank you!
Mark

[Mark53]

What's the problem?
I renamed a Test.XLSX file to Test.XLSB and Excel wouldn't open it.
I renamed it again to Test.XLSX and it opened nicely.

An XLSB file is normally a Microsoft Excel 2007 Binary Workbook for Microsoft Excel 2007.

Maybe you should attach the problem file.

Good luck.
Mark53

[ncngrr5]

Mark53, here is that file, I am not having any luck converting it back to xlsx, thanks again Mark

[Mark53]

I dunno'.
I have Excel 2007; tried to open the XLSB file; didn't work.
Renamed it to an XLSX file; tried to open it; didn't work.
I give up. Sorry, Dude. I'd guess that the file is corrupted.
Good luck.

[Mark53]

The OpenOffice program will open your file, but there's nothing readable in it.
Again, I think the file is corrupted. Good luck.

[ncngrr5]

Mark53,

Thank you for your help, I have been very suspicious whether about the there being anything left file because it was shown as so small,
its an excel spreadsheet I have been adding data to daily for years. Now I am trying a program called Disk Drill to recover old excel files,
I have gone through and opened almost 5000 old files trying to find a current copy, no luck yet. Mark