Start pc and showing black screen press alt+ctrl+delete button then open task manager
click file select new task create new task type explorer.exe
click ok know windows screen will come then open cmd as a administrator and type sfc /scannow
and scan full system after reboot system ok
note: some windows if you open cmd automatic restart system so plese scan full syatem kvrt tool is the best kvrt full scanning take time but system 100% ok
Download Kaspersky Virus Removal Tool (KVRT)