RAR files found on "cracking" or "black hat" forums are notorious for containing Trojans, keyloggers, or info-stealers.
Upload the file to VirusTotal to see how dozens of different antivirus engines categorize it. NetGhost_v1.4.rar
If you must examine this specific file, do not open it on your primary computer. Follow these professional malware analysis standards: RAR files found on "cracking" or "black hat"