eMail Extractor was designed to process plain text files only. As a result, eMail Extractor is not able to process native Excel 'xls' nor native Word 'doc' files directly. In order to extract e-mail addresses from an Excel sheet or a Word document, you have to save it as a plain text file first:

 Excel
- Open your Excel sheet
- Select the 'File | Save As...' menu.
- Select 'Text (Tab delimited)' from the Format pull-down menu.
- Give a name and press the Save button.
- Drop the file to eMail Extractor.

 Word
- Open your Word file.
- Select the 'File | Save As...' menu.
- Select 'Text Only with Line Breaks' from the Format pull-down menu.
- Give a name and click on the Save button.
- Drop the file to eMail Extractor.

That applies to any file saved as a proprietary binary.