SFC can analyze and fix corrupt files in Windows PC. However, for SFC to work correctly, all the components or core files should be working. So, if SFC is not working as expected on your PC, you must first use DISM to patch faulty files in the component store of the Windows system. Then you can run the SFC tool. On top of this, DISM works with VHD and System Images, while SFC only works on an existing system. If you are confused about which one to run first, then it should be SFC first and then DISM if the former doesn't work as expected.