Hi MannyR,Can you make sure that the 'CVI Support' feature of the NI-CAN installer was turned on? What version of CVI are you using? See KnowledgeBase article # 2V27R4HR (<a href="http://digital.ni.com/public.nsf/allkb/E01EF8B67CB49A4C86256CDE0051DF66" target="_blank"> What is the Latest Version of NI-CAN That Supports My Version of LabVIEW or LabWindows/CVI?</a>) for NI-CAN/CVI compatibility. When you have CVI open, is the NI-CAN entry in the libraries menue solid or grayed out?Further more, NI-CAN can support only one version of CVI at a time. Typically that is the latest version found, unless you have already NI-CAN support for an older version of CVI installed. (also see this issue with the NI-845x software: <a href="http://forums.ni.com/ni/board/message?board.id=180&message.id=36256#M36256" target="_blank"> USB-8451 No longer works with CVI 8.5.1</a>). -B2k<a href="../view_profile?user.id=111300" target="top" class="auth_text" style="font-weight: bold;"> </a>