When I try to run Mach3 It just crashes and restarts my computer.

What Windows version are you running? I have heard of a windows update that crashes Mach3. Try uninstalling Mach3 then re-installing it to see if that works. Make sure to save your .xml files under the Mach3 folder or you will lose your settings. Also, copy your license file under that folder so you can re-copy it into the new folder. Another solution is to roll back the windows update to a previous version (just prior to the update). Additional Information: Additional Information: