Try extracting the contents using 7-Zip or the 7z x command. If prompted for a password, look for clues in the challenge description or related files. Password Cracking (If Locked) If the archive is encrypted: Extract the hash using 7z2john.pl .
Once open, the archive often contains: Hidden Files : Files with a leading dot or marked as hidden. RainPouring.7z
Run or Hashcat against the hash using a wordlist like rockyou.txt . Try extracting the contents using 7-Zip or the 7z x command