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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 found a way after it happened to me! I have an Excel that I save on iCloud and I opened it on my iPhone and after I got this message.
On your Mac, right click on the file with the message and open it with numbers. It will ask you to see old versions to restore, choose an older version.
Hope it helps you !
OK, so it solved itself on my machine.
After opening up an excel document on the IOS version of excel, it saved it to 66kb and made it an Open XML document vs excel after I made one slight edit.
It was saved to iCloud overwriting the xlsx extension I had originally on the file (which normally I only edit on my Mac).
I read on another post that someone solved the issue by using Numbers to open the file. So I opened the corrupt file (from iCloud folder) in Numbers and then chose 'Revert to'. It somehow found the version I had previously in a Cloud cache file from the day prior (which was the copy I had made the last edit) and it opened fine in Numbers. I then exported to an Excel file and placed it in the same iCloud folder as the original file (with a different name - I appended 'fixed version' to the filename).
Now I can open that file in Excel....but here's where it got interesting. After opening that file, I was given a warning about opening the file and I ignored the error and it opened fine. But then I went back to the old 'corrupt' file (which I renamed back to an xslx extension) and that version opened with the slight edit I had made yesterday.
So, not sure what bug this is in excel but after going through that exchange, I can open both the repaired/fixed file and the original file which is no longer corrupt. Until they sort out this mess, I won't open anything in IOS.
I want to thank you very much for this clear explanation. I had the exact same issue where my Excel file got reduced to 66Kb after editing it on my iPad and saving on iCloud. It became "corrupted". Hopefully, I was able to save the file using Numbers the way you described it so eloquently. Kudos to you!
The same thing has happened to me. To say I'm pissed off is an understatement. I've lost financial information that I need for my tax records. There doesn't appear to be any way of recovering the file as Numbers freezes when I try to 'browse all versions' on my Mac. Pathetic that this issue has been going on for months with no warnings from Apple or Microsoft
Jonathan OO how where you able to open the file in numbers? My "numbers" iOS App states " table could not be imported" when trying to open from iCloud. Unfurtonately I do have only an iPhone but no Mac.
I am having the same issue, been testing tonight and if I save a file on iCloud then open on phone. if I put anything in any cell as soon as I come out of the document it corrupts the file.
I can then no longer open it in on the Mac or the phone.
One way round it is to save a copy on the phone. I have found that this works for the first time, but would need you to re-save a copy every time you want to edit it.
I first noticed this yesterday