Why is Office Excel having issues in using xlxs files but not with xls

Jake Robert Ventura

Hi, I have observed that using the same file with the exact same data, there's a high chance that using xlsx files have a tendency to spawn the error below: 

 

We can't preview this file. You'll have to download the file to view it.

 

This is also most likely to happen when your file is 2MB or more.

Then when you convert your file to xls and used it in Office Excel, it works just fine. Is there a reason why this is happening ?

Lucas Modzelewski _Lumo_

Hi @Jake Robert Ventura , welcome to the Atlassian Community!

I've checked with Chat GPT, and basically .xlsx is more complex, here is part of the looong response:

 

• XLSX is a more complex and modern format that is XML-based and typically compressed in a zip-like structure. When dealing with large files, especially those over 2MB, this complexity can make it harder for some applications or web-based viewers to process the file for preview.
• XLS, on the other hand, is an older, binary format. It is less complex than XLSX and often simpler for programs to read or preview, especially for larger file sizes, despite XLS files generally being larger in size.

 

It looks like long time ago there was an issue with .xlsx files > 2MB previews on Confluence:

https://jira.atlassian.com/browse/CONFCLOUD-25709