Microsoft Excel not working on macOS Catalina I have Microsoft Excel 2011 installed on my MacBook Air. It worked on Mojave’s but no longer works on Catalina.

When attempting to open an Excel file on my desktop it usually opens but now archives it instead.

Why is this?
The issue is macOS Catalina no longer supports 32-bit apps, and Microsoft Office 2011 is 32-bit. Support for it was stopped a few years ago and it won’t be updated.

You will either have to buy a newer version of office or use an alternative software like G Suite by Google.