What is the VIR file format?
.vir (Virus-Infected File) is a suffix added by antivirus software to files identified as infected. For example, an infected file document.doc will be renamed to document.doc.vir. A similar mechanism is used by many antivirus programs - chiefly Norton AntiVirus historically - and changing the extension of an infected file prevents it from being opened either manually or automatically, since the operating system no longer recognizes its original type.
Managing .vir files
.vir files should not be opened as-is, or after manually changing their extension back to the original. The most secure way to handle such files is directly through the antivirus program's quarantine interface. The possibility that a file was falsely tagged by antivirus software as infected exists, but such events are not frequent. Damages caused by opening a .vir file can be irreversible.
.vir renaming is a legacy behavior. Modern antivirus products - including current Norton (Gen Digital), Kaspersky, and Microsoft Defender - now move infected files into encrypted quarantine vaults rather than simply appending .vir. Encountering a .vir file today typically indicates an older AV installation or a simpler scanning tool that still uses this convention.
Security & safety
RISK: HIGHDANGER: A .vir file contains malware or a file suspected of containing malware. Do NOT open it, do NOT rename it to its original extension, and do NOT send it to others. Use your antivirus console (Norton, Kaspersky, Avira, or Windows Defender) to either permanently delete it or restore it if you are certain it is a false positive. If you received a .vir file from someone else, do not execute it - scan it with an updated antivirus or use VirusTotal (https://www.virustotal.com) for a second opinion before taking any action.
Format details
in a nutshell- Generic infected/suspicious file marker - Other antivirus tools (Avira, older Kaspersky builds, and various freeware AV) have also used .vir as a quarantine or infected-file marker.
Programs that open VIR files
Windows4 apps
Avira Antivirus
Freemium Open Avira → Protection → Quarantine to manage detected threats including .vir-tagged files.
Norton AntiVirus (Norton 360 / NortonLifeLock)
Paid Open Norton → Security History or Quarantine → locate the .vir entry → choose Delete or Restore (only if confirmed false positive).
Kaspersky Anti-Virus (Kaspersky Standard/Plus)
Paid Open Kaspersky → Reports → Quarantine → manage the infected file entry there.
Windows Security (Microsoft Defender)
Built-in Windows Security → Virus & threat protection → Protection history → manage quarantined items. 
macOS1 app
Norton AntiVirus for Mac
Paid Open Norton for Mac → Security → Quarantine to manage .vir-flagged files. Technical details
deep spec| File type | Renamed copy of the original infected file; not a distinct format |
| Extension mechanism | Appended to the original filename (e.g., document.doc becomes document.doc.vir) |
| Internal content | Identical to the original file; no transformation in legacy Norton .vir renaming |
| Magic bytes | Depends entirely on the original file type; no fixed signature |
| Encoding | Same as the original file (binary or text) |
| Typical size | Same as the original infected file; bytes to hundreds of MB |
| Primary historical origin | Norton AntiVirus (Symantec); convention also adopted by other legacy AV tools |
| Encryption | None in legacy .vir renaming; modern AV quarantine vaults encrypt contents |
| Current status | Legacy convention; current Norton, Kaspersky, and Microsoft Defender use encrypted quarantine vaults instead |
| Risk of opening | Same risk as the original malware; do not open or manually rename |
| Restoration path | Use the antivirus program's quarantine review and restore interface |
| False positive handling | Rare but possible; AV software provides review and restore options before permanent deletion |
| Operating systems | Windows primarily; macOS (Norton AntiVirus for Mac and others) |
| Released | circa 1990s (early antivirus practice) |
Community Q&A
asked by usersNo questions yet - be the first to ask about VIR files.
