Excel cannot open file due to invalid file format or extention. File name has been changed to .~lock

Occasional Visitor

Hi there! Would love some help with this one.


I was working on this worksheet when my pc crashed and has to restart. I click the file again and excel crashed.

Then, then I restarted, file name was changed to .~lock.Tomt testskjema ny.xlsx(new additions to the file name in bold).

I changed the file name to its original name; 'Tomt testskjema ny.xlsx'. I then get the 'Excel cannot open the file <filename> because the file format or file extension is not valid. Verify that the file has not been corrupted and that the file extention matches the format of the file.


I have tried change file extension and 'open and repair' feature, with no luck.


Any tips would be greatly appreciated.


Could not attach the file, due to the below error:

  • The attachment's tomt testskjema ny.xls.xlsx content type (application/vnd.openxmlformats-officedocument.spreadsheetml.sheet) does not match its file extension and has been removed.
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