The fsfilter.sys file is the process called F-Secure File System Filter for Windows used by the application F-Secure Gatekeeper developed by F-Secure Corporation. This process file is a driver. A driver is an application that enables your computer to interact with connected or hardware devices. This is not a visible program. The fsfilter.sys file is not a core file for Windows. This process file has a digital signature from F-Secure Corporation with certificate issued by Symantec Time Stamping Services Signer – G3. This process automatically starts on drivers installed. F-Secure Internet Gatekeeper blocks malware and viruses before spreading to end-user desktops and corporate servers. It stops the spread of malware through file transfers, E-mail and Web traffic. It increases productivity and safeguards IT infrastructure. It enables anonymous Internet traffic. It stops encrypted viruses by decrypting and scanning encrypted ZIP files.

Most non-system processes that are running can be stopped because they are not involved in running your operating system. fsfilter.sys. is used by F-Secure Gatekeeper, If you shut down fsfilter.sys, it will likely start again at a later time either after you restart your computer or after an application start. To stop fsfilter.sys, permanently you need to uninstall the application that runs this process which in this case is F-Secure Gatekeeper, from your system.

After uninstalling applications it is a good idea to scan you Windows registry for any left over traces of applications. Registry Reviver by ReviverSoft is a great tool for doing this.

The ReviverSoft experts have not yet reviewed fsfilter.sys

A process usually a part of an installed application such as F-Secure Gatekeeper, or your operating system that is responsible for running in functions of that application. Some application require that they have processes running all the time so they can do things such as check for updates or notify you when you get an instant message. Some poorly written applications have many processes that run that may not be required and take up valuable processing power within your computer.

We have not received any complaint about this process having higher than normal impact on PC performance. If you have had bad experiences with it please let us know in a comment below and we will investigate it further.

The first thing you should do if fsfilter.sys. is causing errors on your computer is to run a Windows registry scan with Registry Reviver If you are still seeing errors after this you should uninstall the program that fsfilter.sys, belongs to, in this case F-Secure Gatekeeper