I have to work with an old application that can only export XLS files and I write programs in .Net using the EPPlus library that is only capable of reading XLSX files.
What is the easiest way to batch convert from XLS to XLSX?
I'd recommend using a macro to process the files within a folder to convert them from xls to xlsx. This code assumes that the files are all located within one folder and that all xls files need to be converted, but if you wanted to select individual files this code could be updated.
This code would need to be run from an Excel 2007 or Excel 2010 workbook.
If the files you are converting contain macros then you would need to update the 'FileFormat:=51' to read 'FileFormat:=52'. Or if you don't need to macro code in the converted files you could leave it alone and it will remove the macros when it converts it to the xlsx format.
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