Mom-in-law needs HELP!

My mother-in-law has a used computer that has windows me....worked fine until she tried to hook up to internet provider (charter cable) then, she says that she got a box saying she must re-load windows, then, comp shuts down...when restarted, only thing showing is the box saying she must re-load windows....she doesn't have any disks with her comp....is comp scrap now or can she get help?