fsmainui.exe is not a virus; it is the "face" of your F-Secure security suite. Unless it is located outside of the Program Files folder or consuming 100% of your CPU indefinitely, you should leave it alone to ensure your real-time protection stays active.
While rare, sometimes fsmainui.exe will spike in resource consumption. This often happens during: fsmainui.exe
The file is a legitimate core executable component of the F-Secure security suite, specifically serving as the Main User Interface for the software. It is responsible for displaying the dashboard, managing settings, and providing notifications to the user. Key File Details Developer: F-Secure Corporation fsmainui
: Users have occasionally reported performance issues or high CPU usage tied to this process. fsmainui.exe is not a virus