The NSA had a hardening guide you could download for free and deploy on a Windows system if you so desired. Following all of the advice in the document was an

The NSA had a hardening guide you could download for free and deploy on a Windows system if you so desired. Following all of the advice in the document was an excellent way to end up with a completely useless system. Worse, thanks to Windows horrible logging infrastructure it was almost impossible to figure out exactly what change was causing a particular bit of breakage. You never EVER get an error message that reads anything like "HKLM\SYSTEM\CurrentControlSet\Services\Ramdisk" : Permission Denied reading key "StartOverride", service halted". Instead it is some generic "the system failed to start" message that doesn't help at all.