Hi Ziaozhongda, You must have the RTX runtime engine installed before the LabVIEW Real-Time RTX module will install. Additionally, you should follow the instructions in the "Using the NI PCI-7831R with the LabVIEW Real-Time Module for RTX" section of <a href="http://www.ni.com/pdf/manuals/323256b.pdf" target="_blank">Getting Started with the NI 7831R</a> (page 8). Please see <a href="http://digital.ni.com/public.nsf/allkb/E2ADBE15D4AB2CC786256F310071BEB1?OpenDocument" target="_blank">Configuring Hardware for Use with RTX.</a> Also useful is "<a href="http://digital.ni.com/public.nsf/allkb/03BC0810E60CE93286256E7D007B61F5?OpenDocument" target="_blank">How Can I Validate That My PC Will Run RTX?</a>