That's pronounced MO-ICE. It stands for Microsoft Office Isolated Conversion Environment, and yes, you should have it.

What MOICE does and why you need it

MOICE uses the converters in the 2007 Office release to convert Microsoft Office binary format files (used in Office 2003 and earlier) into the Microsoft Office Open XML format. This process helps to remove the potential threat that may exist if the document opens in the binary format. MOICE converts incoming files in an isolated environment to help protect against potential security threats.

This helps prevent malicious attacks using potential security vulnerabilities in legacy file formats.

Where to download MOICE and learn more

Read KB 935865 (Description of the Microsoft Office Isolated Conversion Environment update for the Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats). This article provides you with more information, along with installation instructions. These instructions include:

  • Installing the Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats
  • Installing updates that include MOICE
  • Running commands for enabling MOICE
  • Changing some registry settings

This KB article provides the procedures and download locations for each of these steps.

Additional background information

See David LeBlanc's blog post on MOICE for more information about the isolated conversion environment. 

- Andrea Weiss