PIAs are not installed on client machines

The Primary Interop Assemblies are not installed on client machines. This will prevent XWord from starting.
Affected environments:

• Windows machines, without a previous .net framework(1.1, 2.0, 3.0, 3.5) or with .net installed after the office suite
• Custom Windows 7 distribution + Office 2010 installed on top of .net 4.0.
  Note: The .net versions refer to the available platforms during MS Office install, not to the .net version installed by XOffice.

Troubleshouting:

• Download and install the 2007 PIAs from: http://www.microsoft.com/downloads/details.aspx?familyid=59daebaa-bed4-4282-a28c-b864d8bfa513&displaylang=en
• No downloadable PIAs released for 2010 yet. Workarounds: 1) Custom build targeting Office 2010 2)Install step deploying the required assemblies.