Do not use the Tools Manager to uninstall the EarthWork Pro Plugin.
Uninstalling the EarthWork Pro Plugin
To uninstall a Plugin or Starter Pack,
Close PlanSwift
Right-click on the Windows Start button
Select Apps and Features, the Settings/Apps & Features screen opens…
Locate “EarthWorks Pro V3” in the list
Click Uninstall
Follow the prompts to uninstall the Plugin