Excel error "cannot open file because the file format or file extension is not valid."

Question

I am trying to open an xlsx file (I have windows 7) and an error message "cannot open file because the file format or file extension is not valid." I have tried renaming without the x, and also opening in a different version of excel, but the programme will not let me. Any ideas? I'd really appreciate any help!

Answer 1

With Excel 2007, I would first try to open the file in Open and Repair mode.

1. Create a copy (with the original file extention) and note the location.
2. Open Excel with a blank workbook. Optionally close the blank workbook.
3. Click the Office button, then Open.
4. Navigate to the copy of the file you created earlier and highlight it (e.g. single click).
5. In the lower right area (left of Cancel) there is an Open button with other options available from the drop arrow at the right side of the button. ChooseOpen and Repair.
6. When asked about Excel can perform checks..., select Repair.

Did that rectify the problem? If not you may have to repeat the process selectingExtract data instead to get all values and formulas in order to reconstruct your work.

*see also:*Repairing a corrupted workbook

*http://office.microsoft.com/en-us/excel-help/repairing-a-corrupted-workbook-HA*

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Answer 2

Thanks very much for your reply. I tried that, but when I hit "open and repair" now it tells me "cannot access read-only document ...." This doc has never been read only so I don't realy understand this. Do you know why?

Thanks!

Answer 3

If you are now getting the "cannot access read-only document ...." message, this could be due to one or more of the following (by no means a complete list unfortunately):

1. The file has been marked as Read Only. Solution: check/change with right-click,Properties (I know you stated it wasn't, but I want to be thorough)
2. The folder the file is stored in is Read Only or you lackpermissions or possibly a network error. Solution: check/change the folder with right-click,Properties or contact a network administrator
3. A corrupt temporary image is residing within the folder used to store Excel's temp files. Solution: clear the temp directory(ies) withWindows key+R, type in %temp%<enter>, then erase everything in the new folder. May require a reboot if any files are 'stuck' from previous access attempts. A reputable freeware program like CCLEANER will do this for you.

If that last option is correct, it also himts at your original problem.

You may also wish to try starting Excel in safe mode. Use theWindows key+R to open the Run box, then type inexcel /safe <enter>. Repeat the steps for Open and Repair as above.

I sincerely hope something here clicks into place as I'm starting to run out of ideas.

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Answer 4

I suspect it might be about permissions - sorry to ask again, but how do I change that? Is it in properties?

Thanks for all your help so far!

Answer 5

Matthew,

If you can locate the file/folder in Explorer, right click then Properties. File/folder access and/or restrictions are handled under theSharing and Security tabs.

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