Sorry I wasn't being very clear either. I was assuming that you were trying to follow option 2 from Joe D's post on 3-24-2004. Once you know what environment variables have changed you can go the control panel to set them. Some of them will may be new variables that you will need to define. Others may already exists in which case you want to append to them.
The other option is as Joe D said, which is to run VCVARS32.bat before you start Xmath. You could even make a batch file such that instead of starting xmath.bat directly you call your own batch file (.bat). This batch file would have two lines. One to run VCVARS32.bat and the second to run XMATH.bat. If you are not familiar with batch files there are a lot of resources on the web about them. In this case all you would need is:
<path to vcvars32.bat>\vcvars32.bat
"C:\Program Files\National Instruments\MATRIXx\bin\xmath.bat" -v 71.6
The -v 71.6 is optional. it specifies to specifically open version 7.1.6. If you leave it off the newest version will be opened.
Carl L
National Instruments