I have an older Emachines desktop (T5246) with windows vista as the operating system. One day I went to start up the computer and has a windows error recovery. "Windows failed to load because system registry file is missing or corrput. This computer did not come with a operating system disk or any backup disk for that matter. Is this computer fixable or is it done for? Is there a way to correct this problem without having to purchase a new operating system windows disk?