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XLSX File Format

Microsoft Excel Open XML Document

XLSX is a file extension for an open XML spreadsheet file format used by Microsoft Excel.

Microsoft introduced the open XML standard to Microsoft Office in 2007 after a push from business users who saw the value in an open file format for transferring data between applications and other areas of working with the files. Support can also be added to earlier versions of Excel with Open XML component support.

MIME type:  application/vnd.openxmlformats-officedocument.spreadsheetml.sheet



Learn more about XLSX files:

Visit the Microsoft Excel webpage.

Wikipedia has an entry on Office open XML.

Search for answers to XLSX-related questions at IT Knowledge Exchange.

This was last updated in July 2010
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.xlsx file sent as e-mail attachment. Receiver's e-mail program (or some security?) apparently deleted same as it was not received (and did not go into any trash folder). Converted to .pdf and it -was- correctly received. Original file scans with no problem with Jotti's amd Virustotal.
I have just bought MS Office the latest version and assumed that when someone sent me an e mail with an XLSX attachment that I would be able to open it...I can open it but it is text that is entirely undecipherable - what can I do ?



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