How do I remove crashplan from my Mac
Since Crashplan runs with elevated / non-standard permissions for an ordinary app, you will want to:


Reinstall the same or newer version of the software to correct whatever changes non-standard or half-removed. (Free download from http://www.code42.com/store/)
Run the uninstaller that is inside the package contents of the app. (Documented https://support.code42.com/CrashPlan/Latest/Getting_Started/Uninstalling_The_CrashPlan_App)
Optionally delete these two folders if they exist:


~/Library/Application Support/CrashPlan
/Library/Application Support/CrashPlan