Most likely, you did not include the required libraries in your build script. When building an executable in which you use the Report Generation Toolkit, you must include the _Word Dynamic VIs.vi from _wordsub.llb and _Excel Dynamic VIs.vi from _exclsub.llb as dynamic VIs on the Source Files tab.
Check this article for more info.
http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/86256a47004e16d186256a84004cb883?OpenDocument
Daniel L. Press
PrimeTest Corp.
www.primetest.com