• Disconnect all measurement instruments (if connected)
• Disconnect your dongle (if connected)
• Un-install 'i1Profiler' using System's control panel function which can be called 'Add/Remove Programs' or 'Software' or 'Programs'
• Un-install all 'X-Rite Devices (XRD)' using System's control panel function which can be called 'Add/Remove Programs' or 'Software' or 'Programs

Note: the un-installation procedure above does not delete the folder for Assets and Workflows savings installed and used by i1Profiler, because it can contain custom data. If you really want to delete it, please move it manually to the trash (you might want to save a copy first). The folder can be found here:

Windows XP:
C:\Documents and Settings\All Users\Application Data\X-Rite\i1Profiler

Windows Vista and 7:
C:\ProgramData\X-Rite\i1Profiler

Additionally, i1Profiler generates a couple of helpful Log Files. If you want to delete them, review this article.