Dear Margie Stone,
Thanks for visiting Microsoft Community. I am happy to help you.
I understand that you want to retrieve your Excel file after updating your MacBook Air.
Due to the limited information I have learned, I am unable to provide you with an accurate recommendation. In order to better understand and resolve your issue, I need to confirm some information with you:
- I am sorry that I did not understand your question, your Excel file disappeared after the update, so you could not find it? Or did something else happen, can you provide a little more detailed information?
- Are all your Excel files not opening or just individual Excel files?
- What is your system version after updating your MacBook Air? Is your account type a personal or business account?
There are some methods in this article that you can refer to:
Unable to start Excel for Mac - Microsoft 365 Apps | Microsoft Learn
Looking forward to your reply.
Miyeon.S - MSFT |Microsoft Community Support Specialist