Go to VirusTotal and upload the file (or its hash if you have it). It will scan the file against over 70 antivirus engines to see if it has been flagged as malicious.
If the file was part of an unsolicited email or a popup download, it is highly likely to be a Trojan or ransomware. Common Characteristics of Such Files 2929529507.rar
Where did you this file, and have you already tried to open it ? VirusTotal - Home Go to VirusTotal and upload the file (or