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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.
I am having the same issue. 5th File corrupted today and microsoft support is unable to help. Frankly I am at my wits end. It is appalling that no on at Microsoft or Apple can pull this together and solve it. I’ve used Excel for c30 years and Apple for as long as I can remember.
Ok, so after about 5 hours of trying various things, this is what actually worked! Thank you so much, I was so gutted when I thought I lost my file!
The bit I was stuck on was getting Numbers to revert to a previous version of the file, as it kept crashing when I tried that. So then I deleted the Numbers app and reinstalled it, and I could then recover the old version of the file and save it.
This is a total disaster. I lost a file with extremely importa data. Now is 66kb and cannot open anywhere as iCloud has replicated all over the many devices. what can I do??
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.
Same issue. Opening Excel file on iCloud drive from IOS/iPhone, file gets corrupted. Currently no way to recover other than through backups.
Error message
"Excel cannot open the file 'file.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."