It's a system kernel driver, aka "AFD Networking Support Environment" and is part of the Windows TCP/IP stack, supporting socket operations.
Important: Some malware disguises itself as afd.sys, particularly when
not located in the C:\Windows\System32\drivers folder. Therefore, you should check the afd.sys process on your PC to see if it is a threat.
A clean and tidy computer is the key requirement for avoiding problems with afd. 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 afd.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.