Capitalized File Extension???? Why and How to Change from ".XLSX" to ".xlsx"

[AlexB123]

I have an excel file that is saved with a capitalized extension, "XLSX". I've tried to resave the file with a lowercase "xlsx" extension, but I am unable to do so. I've checked in the options and settings, and searched online for an explanation, but have had no luck.

Can anyone tell me when and why files get saved with a capitalized extension? Also, how can I change to the lowercase extension?

Thanks,

 

[jmacleary]

Hi there. I assume you are using windows, which for largely historical reasons doesnt differentiate between upper and lower case all the time. So, instead of using save as, use file explorer to edit the extension directly. The cahnge will then stick. You may need to change your view setting to show file extensions.

 

[AlexB123]

Thank you, @jmacleary. This worked!