Let's start at the begining.... everything was working fine, and then I started getting an error 2 (memory is full) while compiling any application. I couldn't resolve the issue but the same applications would compile on another machine, so I uninstalled every National Instrument software from Control Panel (add remove programs), and deleted the c:\Program Files\National Instruments directory. I then reinstall the Labview 8.0 Prof Dev system, and performed the labview 8.0.1 upgrade. I can now open and compile applications, but now when I try to run one of the compiled applications it says it can't find the labview 8.0 or compatible run-time engine.... I tried to install the runtime engine, and I get an error message saying a higher version is already installed so it won't install.... when I go to control panel the runtime engine 7.0 and 7.1.1 show up , but Runtime 8.0 or 8.0.1 do not.... I installed runtime 8.2.1 to see if it would show up in the control panel 'add remove programs) and it does not .....