For ESET Smart Security users, the 803191 error was sometimes triggered by the built-in firewall blocking the program’s own activation traffic. The fix introduces a permanent, hidden allow-rule for licensing domains, preventing self-blocking.
If you are running an older version with this build number, the "proper feature" is automatic startup protection. However, you should note that ESET no longer supports NOD32 v10 or Smart Security v11 (support ended in 2020/2021). To get current features (Anti-Ransomware, Exploit Blocker, Home Network Protection), you should upgrade to ESET HOME Security Essential or Premium (v17+ as of 2026).
ESET NOD32 Antivirus and Smart Security 8.0.319.1 was a specific maintenance release primarily focused on ensuring compatibility with modern operating systems and internal security hardening. Key Updates in Version 8.0.319.x
Windows 10 Compatibility: Added full support for the Microsoft Windows 10 RTM build 10240, ensuring the security suite functioned correctly on the then-new OS.
Security Hardening: Improved internal product security to better protect against targeted attacks aimed at the antivirus software itself. eset nod32 antivirus and smart security 803191 fixed
Optimised Performance: Refined internal code for better efficiency and lower system resource usage.
Direct Build Integration: Included the latest virus signature databases and modules directly within the installation build for immediate protection upon setup.
License Updates: Introduced a revised End User License Agreement (EULA). Core Version 8 Features
While 8.0.319 was a specific build, it retained the landmark features introduced in the version 8 series: For ESET Smart Security users, the 803191 error
Botnet Protection: Specialized technology in Smart Security that detects and blocks malicious network traffic associated with botnets.
Enhanced Exploit Blocker: Safeguards against attacks on web browsers, PDF readers, and Java-based software, specifically designed to eliminate ransomware and lockscreens.
ESET SysRescue Live: Allows for the creation of a bootable Linux-based recovery disk (USB/CD) to scan and clean systems that cannot boot into Windows.
HIPS Smart Mode: An Advanced Host Intrusion Prevention System that only triggers notifications for suspicious system events, reducing user interruptions compared to Automatic mode. Current Status If you have followed all five methods above
End of Life: ESET Smart Security 8 reached its official end-of-life in February 2019.
Successor: It has since been replaced by modern all-in-one plans like ESET HOME Security which include advanced features like AI-powered threat detection and multi-layered ransomware defense.
If you have followed all five methods above (cleared cache, verified time, checked firewalls, reset hosts, and performed a clean reinstall) and you still see error 803191, the problem may be on ESET’s side or related to a deep system-level conflict. In this case:
ESET support has server-side tools to verify if your IP address is being blocked or if there is a regional distribution issue.