sethc.exe is a process associated with Windows NT High Contrast Invocation and is part of Microsoft® Windows® Operating System. With default Windows settings, this process is run when the shift is pressed 5 times in sequence, to invoke the StickyKeys configuration window.
Non-system processes like sethc.exe originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that over time your registry suffers fragmentation and accumulates invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues