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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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I have been successfully using OneDrive on my PC, iPhone and iPad Pro while editing the same spreadsheet. It doesn't appear the O365/iCloud issue will be resolved in a timely fashion so I recommend using OneDrive.
That’s just it. I was using OneDrive. Then they added the 365 app and that’s when things went sideways. I mention iCloud since I believe it’s all related somehow, but I’m not a tech, and no one from OneDrive, MS, or Apple seemingly has had no interest in fixing this. Every day I do the same thing open a file, close a file, reopen. Never change name, location, delete. Yet, they got deleted, and I never saw them in recycle till I got the late night email from an Escalation Manager from MS (only contact I ever got) saying you have 2 hours left to move them back, or they’re gone forever. That’s the only time I saw them in Recycle, that was May 12, 29 days + ~20hours after they initially disappeared.
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 was the definitive answer to the problem! I also deleted and reinstalled Numbers and used this approach. For months I’ve had problems with Word and Excel [MS 365 versions] on iPad corrupting files when saving to iCloud. I hope MSFT and/or Apple fix this, but if you run into the issue, this is the path to recovery.
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!