Hi George,
This is is usually the result of some error in the driver install process. The easiest way to fix this normally is to close all National Instruments Products (MAX, LabVIEW, CVI, Teststand and so). Then temporarily disable anti-virus software, and registry protectors like Ad-Aware or Spybot.
Next go to My computer >> Control Panel >> Add/Remove Software >> National Instruments Software and click on change. find NI-DAQmx 8.0.1 and select this an choose Repair.
This will launch the installer and take you to the components to install page. Make sure you have selected support for LabVIEW 7.1 Click Next through the different menus until the install finishes and then restart the computer.
When the computer restarts, open LabVIEW 7.1 and the DAQ Assistant should work as expected.
Regards
JamesC
NIUK and Ireland