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Verify that the file has not been corrupted and that the file extension matches the format of the fi
Excel cannot open the file 'filename.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 fi...
When you get the error, does it let you click to continue on, and open the file anyway? I get this alert also, but I am able to click past it and then I do a save as. Then I noticed the file type that Excel thinks it is.....mine is a .html file type originally, so I change the file type to .xlxs and I am good to go.
No cannot continue