In excel what does a file ending with .xlsx mean?

[pdog1967]

I have created and saved several files in Excel. I then sent them to a friend
at a different company. I was then notified that they could open all of the
files that were .xls but the one that was .xlsx they could not open. How did
I get the file saved with the extra x, and what does that mean?

 

[PJFry]

..xlsx is a Excel 2007 format, whereas .xls is Excel 2003 or earlier.

Excel 2007 allows you to save in multiple 2007 formats:
..xlsx - Normal Excel 2007 format
..xlsm - Macro-Enabled format
..xlsb - Binary format

Save your files as 2003 under Save as Type and you should be fine.

PJ

 

[pdog1967]

Thanks, I thought that I had saved them all the same, guess not.