National Instruments NI-CAN User Manual page 72

Appendix C Windows NT: Troubleshooting and Common Questions
NI-CAN User Manual
Why does the uninstall program leave some components installed?
The uninstall program removes only items that the installation program
installed. If you add anything to a directory that was created by the
installation program, the uninstall program does not delete that directory,
because the directory is not empty after the uninstallation. You will need to
remove any remaining components yourself.
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