Run a deep scan using updated antivirus software (like Windows Defender or Malwarebytes) on the folder containing all parts before attempting extraction.
Games distributed in this format often require "cracks" or bypassed executables, which are frequently flagged as Trojans or Ransomware. DOOM.part05.rar
Downloading and opening multi-part archives from unofficial sources carries significant risks: Run a deep scan using updated antivirus software