You need to have MultiTerm or Trados Studio (2009 or later) installed on your machine, if you want to write sdltb files. You can actually read them without any 3rd party software required.
If you want to read or write Excel files (xls/xlsx), you also need Microsoft Excel (2003 or later), or either LibreOffice or OpenOffice. For these last 2, only the 32 bit versions work, not the 64 bit releases. You can use tab separated txt, or csv files without any 3rd party software.
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