This article explains what an XLK file is and how to open or convert it.
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A file with the XLK file extension is a backup file created by Microsoft Excel. It is created automatically while an XLSX or XLS file is being edited.
Excel does this in case something goes wrong with the document. For example, if the file is so corrupt that it can no longer be used, the XLK file acts as a recovery file.
XLK files can also be created when exporting information from Microsoft Access to Excel.
