Forum Discussion

fe_capella16's avatar
fe_capella16
Copper Contributor
Mar 01, 2026

File always corrupt

Anyone have the same problem with me? I use microsoft excel 365 on my mac. At the beginning everything alright, until i use formula and then save the file. When i want to re-open the file, the messag...
excel
Excel on Mac
Formulas and Functions
office 365
NikolinoDE's avatar
NikolinoDE
Platinum Contributor
Mar 02, 2026

I completely agree with mathetes; those diagnostic questions are spot on and will help us pinpoint the root cause. However, while you are checking those details, I’d like to offer a few "first aid" steps that commonly resolve this specific Mac/Office 365 behavior.

Since this happens specifically when you save after using formulas, it sounds like a calculation engine hiccup or a file structure issue. Here are a few things we can try immediately to stabilize the file:

 1. The "Binary" Save (Highly Recommended for Mac)

Mac versions of Excel can sometimes be sensitive to the standard .xlsx format (which is actually a zip file of XMLs).

  • Try this: Go to File > Save As and change the file format to Excel Binary Workbook (.xlsb).

 2. Check Calculation Settings

Sometimes, if the calculation mode gets stuck or conflicts with volatile functions, it causes save errors.

  • Go to Excel > Preferences > Calculation.
  • Ensure "Calculate workbook automatically" is selected.
  • Also, check if you are using "Volatile" functions (like OFFSET, INDIRECT, NOW, RAND) heavily. Sometimes these force a rewrite of the file structure upon saving that triggers the error on Mac.

 3. The "Printer" Glitch (A classic Mac quirk)
It sounds strange, but corrupted printer drivers on Mac can cause Excel to crash or corrupt files upon saving.

  • Try this: Go to File > Print. Change the printer to "Microsoft Print to PDF" or "Save as Adobe PDF". Try saving the file. If it works, the issue is a conflict with your default physical printer driver.

 4. Clear the "Ghost" Links
If your formulas reference other closed workbooks or external data sources, Excel might be failing to update the links during the save process, causing the corruption flag.

  • Go to Data > Edit Links (if available) and break any external links you don't absolutely need, or ensure the source files are accessible.

Regarding mathetes questions:
If you could let us know if this happens with new files (as mathetes asked), that tells us if it’s a "Template/File" problem or a "System/Installation" problem.

  • If it’s just one file: The sheet itself is damaged (try copying all data to a new blank .xlsb file).
  • If it’s all files: It might be a corrupt Office installation or a problematic Add-in. (Try holding Shift while opening Excel to start in Safe Mode).

Don't forget no one in this forum can see what you see.

In this link you will find some more information about it:

Welcome to your Excel discussion space!