Npf.sys is a Windows driver. A driver is a small software program that allows your computer to communicate with hardware or connected devices. This means that a driver has direct access to the internals of the operating system, hardware etc. The free file information forum can help you determine if npf.sys is a Windows system file or if it belongs to an application that you can trust.
The process known as npf.sys (NT5/6 AMD64) Kernel Driver or npf.sys (NT5/6 (version x86) Kernel Driver) or NPF Driver - TME extensions or WinPcap Packet Driver (NPF)
belongs to software NetGroup Packet Filter Driver or WinPcap Netgroup Packet Filter Driver or NPF Driver or WinPcap Packet Driver (NPF)
by CACE Technologies (www.cacetech.com) or Riverbed Technology or Politecnico di Torino or NetGroup - Politecnico di Torino.
Description: Npf.sys is not essential for the Windows OS and causes relatively few problems. The file npf.sys is located in the C:\Windows\System32\drivers folder.
Known file sizes on Windows 8/7/XP are 32,512 bytes (41% of all occurrences), 35,088 bytes and 14 more variants.
The driver can be started or stopped from Services in the Control Panel or by other programs. The program has no visible window. The service has no detailed description. The file is not a Windows core file. npf.sys appears to be a compressed file. Therefore the technical security rating is 25% dangerous, however you should also read the user reviews.
You have the option to uninstall the program using the Control Panel ⇒ Add/Remove programs ⇒ WinPcap.
Recommended: Identify npf.sys related errors
Important: Some malware disguises itself as npf.sys, particularly when not located in the C:\Windows\System32\drivers folder. Therefore, you should check the npf.sys process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World.
A clean and tidy computer is the key requirement for avoiding problems with npf. This means running a scan for malware, cleaning your hard drive using cleanmgr and sfc /scannow, uninstalling programs that you no longer need, checking for Autostart programs (using msconfig) and enabling Windows' Automatic Update. Always remember to perform periodic backups, or at least to set restore points.
Should you experience an actual problem, try to recall the last thing you did, or the last thing you installed before the problem appeared for the first time. Use the resmon command to identify the processes that are causing your problem. Even for serious problems, rather than reinstalling Windows, you are better off doing a repair of your installation, or in the case of Windows 8, executing the DISM.exe /Online /Cleanup-image /Restorehealth command. This allows you to repair the operating system without losing data.
To help you analyze the npf.sys process on your computer, the following programs have proven to be helpful: Security Task Manager displays all running Windows tasks, including embedded hidden processes, such as keyboard and browser monitoring or Autostart entries. A unique security risk rating indicates the likelihood of the process being potential spyware, malware or a Trojan. Malwarebytes Anti-Malware detects and removes sleeping spyware, adware, Trojans, keyloggers, malware and trackers from your hard drive.