Office 365 iOS App Corrupted Excel File

Anonymous
2023-03-18T18:37:50+00:00

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

Microsoft 365 and Office | Excel | For home | iOS

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  1. Anonymous
    2023-04-06T14:50:04+00:00

    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.

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  2. Anonymous
    2023-03-19T10:29:31+00:00

    I do not have a solution but I’m experiencing the same thing.

    The thing I have noticed is that I can open an excel file, via icloud, on my Iphone (or ipad) and as long as I don’t make any changes to the doc (put a number in a cel) everything is fine. I clan close the file and open it later on. However, when I have changed/added something in the doc, the file gets corrupted when you go out of the 365app (and saved automatically). The file is useless after that.. unable to be fixed/repaired (at least, with the options I have tried).

    When using the 365app to open, make changes and save an excel file to my Iphone (or ipad), so not via icloud, everything is working as it should be. So no corrupted files after changes are made. When downloading, make changes and save an excel file with pc/mac from icloud all is good as well. So it seems to be a problem specific for iphone/ipad in combination with icloud/365app. But no idea where the source of the problem lies..

    The way I worked with Icloud pretty became useless at this point.

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  3. Anonymous
    2023-04-02T09:14:04+00:00

    100% it’s just the iOS or iPadOS version. I’m using iCloud on my Mac as usual and it’s fine, as soon as I open on the phone and select a cell(don’t even have to type) it corrupts the file down to 66kb. This is a massive issue, does anyone know the best way of escalating this?

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  4. Anonymous
    2023-03-23T02:40:27+00:00

    Any fix for this found yet?

    I am having the exact issue. I opened an XLSX stored in iCloud Drive on my iPhone a few days ago (20th?). As soon as I closed it, I was prompted that the file cannot be opened. Now I cannot access the file from any device - not my Mac, iPhone, not even by downloading it from iCloud.com. This is extremely concerning as it has all of my personal finances on it and with it being tax time...yeah. Not good.

    "Excel cannot open the file 'FILE NAME.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."

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  5. Anonymous
    2023-04-03T08:37:29+00:00

    I have used Numbers on Mac that proposed me to recover older version and I found the non corrupted file...good workaround

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