Here is a batch file for anyone who wants to do this "lazily" @echo off REM Vaccince for NotPetya/Petya/Petna/SortaPetya. echo Administrative permissions required. Detecting permissions... echo. net session >nul 2>&1 if %errorLevel% == 0 ( if exist C:\Windows\perfc ( echo Computer already vaccinated for NotPetya/Petya/Petna/SortaPetya. echo. ) else ( echo This is a NotPetya/Petya/Petna/SortaPetya Vaccination file. Do not remove as it protects you from being encrypted by Petya. > C:\Windows\perfc echo This is a NotPetya/Petya/Petna/SortaPetya Vaccination file. Do not remove as it protects you from being encrypted by Petya. > C:\Windows\perfc.dll echo This is a NotPetya/Petya/Petna/SortaPetya Vaccination file. Do not remove as it protects you from being encrypted by Petya. > C:\Windows\perfc.dat attrib +R C:\Windows\perfc attrib +R C:\Windows\perfc.dll attrib +R C:\Windows\perfc.dat echo Computer vaccinated for current version of NotPetya/Petya/Petna/SortaPetya. echo. ) ) else ( echo Failure: You must run this batch file as Administrator. ) pause