Nothing much that you can do as it strongly suggests that the main input fuse has blown, this of course being a special soldered in type on the main PCB which requires replacing by a person suitably qualified in working with precision pieces of equipment "and" having a fine pointed soldering iron. Although the fuse could have failed through a positive fault having developed they can though occasionally fail for no particular obvious reason as "just one of these things", so its not necessarily a doom and gloom scenario.