If you saved your workbook (.xls) in some older versions of Excel with the backup function enabled, a separate .xlk file was saved as well for backup purposes. This pretty much what xls to xlk conversion does, but it can be only done using certain versions of Excel and cannot be done in latest editions of the program
Convert Microsoft Excel 97 to 2003 workbook to Microsoft Excel backup file.
We found 2 software records in the database related to .xls to .xlk file format conversion.
Microsoft Windows software - convert xls to xlk on Windows
A popular spreadsheet application distributed with Microsoft Office suite
Convert from xls file format
|Yes, Microsoft Excel supports xls file conversion as a source file type.||Yes||Yes||xls editor||Yes||No||No||No|
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned xls to xlk. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert xls to xlk on OS X
A popular spreadsheet application from the Microsoft Office suite