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Hi,
I'm hoping someone can help me with 2 xlsx files that have been corrupted.
I use iCloud to store my documents, I finished working on the 2 files in question on my MacBook in the morning and then later in the day successfully viewed them (not modified) on my iPhone using the Office 365 app.
When I came to open the files again, they are unable to be opened on any device using either numbers or excel. I have tried on my iPhone, MacBook and a Windows 11 PC. The error message is:
"Excel cannot open the file 'ABCDEF.xlsx' 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."
I have tried changing the file extension to xls. I've tried to open and repair the files using Excel on Windows however that hasn't worked either. I've used a couple of trial versions of recovery software and the preview shows the first sheet is there but the remaining sheets aren't which are vital to the spreadsheet.
Does anyone have any ideas or experience of this issue? I've noticed the timestamp of last saved has changed to the date and time I opened them on my phone. I'm not sure why Office365 resaved these files without me making changes or asking me.
Thanks
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Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Same here. The file size gets changes to 66KB and corrupted and no way to open. Very frustrating to lose the data. This has been happening since 2 weeks or so. No problems before. Must be a bug in the app.
It must be an issue with a recent update of the iOS app. I’ve never had this issue in the past, but I saved a file yesterday to iCloud and received the same error when trying to open today.
Thankfully, I have Time Machine enabled on my Mac Mini, so I was able to recover the file from a version prior to the corrupted saved version from yesterday. I lost my recent changes, but at least I didn’t have to rebuild the file from scratch. If you have a Mac with Time Machine, you can try to recover the file that way.
Has anyone managed to work out if this is only isolated to certain scenarios? Like certain versions of iOS, or certain devices compared with certain versions of excel? Am just trying to understand why this not a bigger thing that has been sorted. Are there only a few of us effected? Or is it that people don’t use excel on iOS? Which I find hard to believe!
Same issue here, just lost my xlsx file.
Latest release of iPadOS and Office 365 application with xlsx from iCloud Drive.
Filesize set to 66KB and all data lost... devastated :(
It only happens when you change/update an excel file from an icloud location (to icloud).
As a mac user, and didn’t make changes to the file, you can still download it from icoud to your local drive on your mac and use it as intended. So no corrupted files when using excel on a mac without ciloud.
Don’t know if it has something to do with IOS version etc..