If you’re in any doubt, and think that there might be a virus on your computer, then most security software suites or antivirus programs allow you to do an on-the-spot update to check for the latest threats.
Your security software gives real-time protection against threats as they emerge, but regular system scans are vital.
Any anti-virus software must be updated regularly as virus definitions increase day by day.
Updating Norton anti-virus can be done easily from its interface.
Most updates only involve installing the latest virus database definitions, and this can be a reasonably quick process.