My Excel Budget file... no! [Unable to open file]

[OCDinvestor]

I posted this to the Microsoft community, but perhaps someone here has some ideas.

Excel cannot open the file 'XXXXXXX' because the file format or file extension is not valid. Verify that the file has not been corrupted and that the file extension matches the format of the file.

This has happened to multiple excel files on the same Microsoft 365 for Mac account over multiple days. I even spend all yesterday recreating the slimmed down Budget file, for it to happen again! Help!

**I'm fairly computer illiterate, so please talk to me like a second grader**
**I Googled this issue, but several tech responses didn't seem to be available to me--- like "click the arrow next to Open", but there was no arrow present**

[jayjayc]

What's the file's extension?

edit: re-phrasing for a 2nd grader. what are the letters after the "." in your filename?

[OCDinvestor]

.xlsx

This is being (trying to be) opened on the most up to date Microsoft 365 for Mac.

[jayjayc]

In the original file, did you "save as" and select .xlsx?

Does the file have any macros?

edit: what OS and application was used to create the original file?

[abjadh]

You may want to check Fix#1 through #5 here

https://4ddig.tenorshare.com/office-rec ... valid.html

[mrmass]

Does Excel open at all? If not do a repair or reinstall. If yes save the file to OneDrive then try to open it from an iPhone or iPad. Finally see if google docs can open it. As a last resort try to open it with a Windows machine.

[Raycpact]

I use Excel frequently over the years in business. I have had two times a file was unable to open. Both times I installed "open office" and it was able to open the file and able to file it as an excel file. I see that Open Office is not longer available but it seems to be under Apache Open Office:

https://www.openoffice.org/download/index.html

[tunafish]

Are you switching between systems? I believe xlsx is for a newer excel and perhaps older excels do not like it.

[enad]

There is a known issue with Excel of files being corrupted. Not sure how big your file got but once it reaches a certain size it can break just by opening it. Do you make backups?

[BolderBoy]

I would try installing LibreOffice and using Calc to open the file.

[dukeblue219]

Are you switching between systems? I believe xlsx is for a newer excel and perhaps older excels do not like it.

Xlsx came about in Office 2007 which realistically was a long, long time ago. Anyone using Microsoft 365 would be able to open any valid Excel file even if the extensions were mixed.

[LLeaff]

If your files are stored in oneDrive you might be able to resurrect a previous version...

[rich126]

Haven't had this issue but a few things.

Are you sure the files are spreadsheets? You can also go to the terminal window and navigate to where the files are and type "file filename.xlsx" and it should tell you the type of file.

Can you open the file using Apple's built in spreadsheet, i.e., Numbers?

As someone else asked, can you open Excel itself? Is it possible you have 2 versions of Excel and it is trying to use the older version to open the file?