Corrupt xlsx2csv requires the installation of the Microsoft .Net version 2 framework. Corrupt xlsx2csv will extract and convert to CSV format worksheets from even damaged or corrupted Excel 2007 xlsx format files. It succeeds at doing so where Excel 2007 itself fails to salvage data. The program has a Perl/Tk GUI front end. It can also be simply used as a viewer of the unformatted data in an xlsx file without having Excel 2007 installed.Excel 2007 files are really zipped collections of mostly XML files. XML is not tolerant of file corruption and from the errors generated it appears that Excel 2007 is using a fairly corrupt intolerant XML reading algorithm to even salvage unformatted data from corrupt xlsx format files.Corrupt XLSX2CSV uses an unzipper which is tolerant of XML file corruption and uses Perl coding to extract the sharedStrings.xml and worksheet.xml files where all of the unformatted data resides in a xlsx file. Since this Perl coding does not use a standard XML reading applet or module but identifies the cell data as text or string and extracts, the result is more less perfectly extracted data until that part of the xml files where the corruption starts, is reached. Contrastingly, Excel 2007 appears to return no results for that particular xml file if it encounters any XML errors at all.