The file npf.sys is a packet capture file from WinCap’s Netgroup Packet Filter software. The file supports software applications that capture and export packets throughout a network of computers, without going through standard protocol stack. The process’ fast indexing feature enables fast packet capture for data storage, which then enables the system to check for errors, look for security threats; and ascertain that data communications is performed properly. The file is found to be essential for networks that use virtual LAN. The file may also be used by third-party applications, and disabling it may cause these applications to stop running, or it could compromise their performance. Unless the user is certain that no applications are using the file, npf.sys should be left running on the computer, as per the recommendations of users. The process was tested by online security checkers, and it was determined that the file poses no threat to PC health.

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

A process usually a part of an installed application such as WinCap Packet Filter Service, 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 npf.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 npf.sys, belongs to, in this case WinCap Packet Filter Service