: Legitimate digital distributors (like Steam) or modding communities (like ModDB) do not package files with "DOWNLOAD FILE" in the title.
Genuine game files or reputable mods are almost never named with "DOWNLOAD FILE" as part of the filename. This naming convention is typically used by automated scripts on suspicious websites to trick users into downloading malicious content. Why this is likely a threat: DOWNLOAD FILE – HALF-LIFE: OPPOSING FORCE.RAR
If you want to play the game safely, I recommend using these official or highly-trusted sources: : Legitimate digital distributors (like Steam) or modding