You can roll back an administrative image to an earlier installed service pack. If you installed the SOLIDWORKS software with disks, you need the original disks to restore a service pack. You must have saved a copy of the earlier administrative image.
Administrative images that have been upgraded cannot be rolled back to a previous service pack. Administrative images created with any method other than SOLIDWORKS Installation Manager cannot be rolled back to a previous version. Clients installed from these administrative images must be uninstalled and then reinstalled using an administrative image created from the previous version.