To this extent, not only that you must keep an antivirus with real-time protection capabilities running on the PC, but also make sure its virus definitions are up-to-date.
Like many of its competitors, F-Secure released a manual updater for the virus signatures, offering a solution to updating definitions when the Internet connection is down.
No restart of the program or your computer is necessary after this process is finished.
Manually updating the F-Secure products requires nothing more than the offline updater and a little bit of patience.
Virus definitions contain information that allows your computer to identify and remove all of the latest viruses from your computer.
If your definitions are out of date the program will miss newer viruses which will leave your computer vulnerable to attack even if the results of the scan come up clean.
In this case, the automatic definition updater in each F-Secure product will not work, since it cannot download the signature files from the F-Secure servers.
The FSUpdate utility must be downloaded periodically, transferred to the offline computer and launched with administrative privileges.