To fill in some details about what is going on....
Lagging Microsoft by a few years, NI has dropped support for Windows 2000 in its 2010 software releases. The engine behind the Application Builder is a system component that can get updated when you install new software (because installer technlogy changes over the years, the Application Builder engine must also be updated to keep in sync). And, the Application Builder engine itself no longer supports Windows 2000 as of the 2010 releases.
Putting this all together - what has happend is that you have installed some 2010 NI software on this system that has updated some components and/or drivers to the 2010 versions, which included the Application Builder engine. Because the Application Builder engine is shared by all versions LV installed on the system, installers built by LV 2009 no longers supports Windows 2000 either. This is an unfortunate side effect, but some of the 2010 drivers and/or support files that are built into the distribution possibly no longer support Windows 2000 either, so it's not just an issue with the installer.
There really isn't a workaround besides uninstalling all NI software on the system, then only installing 2009 or earlier versions if you still intend to target Windows 2000.
Regards,
- WesW / NI
