To uninstall Mastercam, there are a few things you need to do to completely uninstall Mastercam.
First, go through the Start Menu, and to Settings. When the Settings come up select Apps & Features then selesct the version of Mastercam ou need to uninstall, and select to Uninstall it.
Going through the C drive to the Users, into your login and to Documents. You can delete or rename the My Mcam folder, this will remove the configuration and workspace files. Renaming the folder will allow you to save your configurations and workspace files to recall them if you need to.
Next back out to the Users folder, go to Public, and Public Documents, and delete or rename the Shared Mcam folder, this folder has the post files, the machine simulation files and tool library files.
Once the Shared Mcam files are taken care of, back out to the C drive and go to Program Files, and delete the Mcam files. You don't need to rename this, if you're reinstalling Mastercam, you want the new install to recreate the files.
With these files deleted, press the Windows key + R on the keyboard to us the Run utility and type in "regedit" to open the Registry Editor.
In the Registry Editor and expand the HKey_Current_User, then SOFTWARE, and under that you'll find CNC Software, Inc. Expand that and select the Mastercam registry you're uninstalling and delete it.
Then collapse the HKEY_CURRENT_USER, and go to the HKEY_LOCAL_MACHINE. Expand SOFTWARE and then CNC Software, Inc. and delete the Mastercam version you're uninstalling.
Once the registries are deleted Mastercam is completely uninstalled