Configure Windows File Explorer to "Show file extensions" to reveal the true file type.

If this is an unexpected or suspicious file, it should be treated as a threat and scanned using security software. Protective Actions (If this is a suspicious file) Do Not Open: Avoid double-clicking the file.

Windows often hides the true extension (e.g., .exe ), causing file.mp4.exe to look like file.mp4 .

Use VirusTotal.com to analyze the file securely.

If you are looking for information regarding a specific, authorized video file or a different context, please provide more details. To help you better, could you please clarify:

What is the (e.g., is it actually .mp4.exe , .mp4.zip , etc.)?

Suspicious samples can be sent to security companies like Kaspersky or ESET.

Knowing this will help me tell you if it's a security risk or a technical issue.