Fixing Windows problems with System File Checker
This video talks through how SFC can be used to fix Windows system file corruptions. While some corruptions (ones that don't concern core system functions such as GUI manager libararies) can be temporarily ignored and sometimes even righted by a restart, others, such as the one talked about in this video, cannot. In most cases, when suspecting a system file error, do not rush to restarting your PC immediately, as this one, for example, can cause the system user interface to never load up again, at which point external sources are needed to remedy the issue.