This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

firefox.exe with system PID listening on tcp 139

  • No replies
  • 0 have this problem
  • 3 views
c.pierce83
c.pierce83
more options

I noticed Firefox listening on port 139. Is this normal? I uninstalled reinstalled and it still does it. This is on a windows 10 computer. My windows 11 computer does not show this. On further inspection the PID for the 139 port is system not Firefox.


Active Connections 

 Proto  Local Address          Foreign Address        State           PID

[firefox.exe] 

 TCP    192.168.1.144:139      0.0.0.0:0              LISTENING        4
I noticed Firefox listening on port 139. Is this normal? I uninstalled reinstalled and it still does it. This is on a windows 10 computer. My windows 11 computer does not show this. On further inspection the PID for the 139 port is system not Firefox. Active Connections Proto Local Address Foreign Address State PID [firefox.exe] TCP 192.168.1.144:139 0.0.0.0:0 LISTENING 4

You must log in to your account to reply to posts. Please start a new question, if you do not have an account yet.