I’m working on a .NET console app that syncs files between local storage and Google Drive. The app uploads Excel files to Google Drive where they get converted to Google Sheets format, then downloads them back as Excel files.
Everything works fine when I open the downloaded files in Excel 2007, but Excel 2016 gives me trouble. When I try to open the same file in Excel 2016, I get this error message:
We found a problem with some content in the file. Do you want us to try to recover as much as we can?
If I click yes, the file opens but shows an error log mentioning something about conditional formatting. Also, any frozen rows from the original Google Sheet don’t stay frozen in Excel 2016, but they work fine in Excel 2007.
I’m using the Google Drive API for .NET to handle the conversion process. Has anyone else run into this compatibility problem? Is there a way to make the downloaded Excel files work properly with newer Excel versions, or should I try a completely different approach?
google’s export format is pretty outdated. export as xlsx instead of xls if ur api supports it - newer excel versions are picky about file structure. also check if there’s a mimetype param for downloads, that usually fixes compatibility issues.
Yeah, this is a classic Google Sheets export bug. Google uses its own take on Excel formatting standards, so the files technically work but throw compatibility warnings in newer Excel versions. I ran into this big time when we migrated our document system. The conditional formatting breaks because Google exports rules that Excel 2016+ thinks are malformed or outdated. Same deal with frozen panes - Google uses old freeze methods that newer Excel doesn’t like. What worked for me was tweaking the Drive API export parameters. Try forcing the MIME type to application/vnd.openxmlformats-officedocument.spreadsheetml.sheet instead of letting Google pick. You could also add a step that strips the problematic formatting before users download the files.
Had the same problem with Google Drive API conversions. Google Sheets messes up certain Excel features when converting, and when it exports back to Excel, it creates formatting that older Excel versions accept but newer ones throw warnings about. I fixed it by skipping Google’s Excel export entirely and using OpenXML SDK instead. Pull the raw data from Google Sheets API and rebuild the Excel file yourself - you get complete control over compatibility. Fixed my conditional formatting warnings and kept frozen panes working across all Excel versions. Yeah, the code’s more complex, but way more reliable in production.