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

Le thread ibilondoloziwe. Nceda ubuze umbuzo omtsha ukuba ufuna uncedo.

My prefs.js file is being automatically rewritten every time FF loads

  • 3 iimpendulo
  • 1 inayo le ngxaki
  • 1 view
  • Impendulo yokugqibela ngu cor-el

S_Kinison
S_Kinison
more options

My proxy settings are being changed every time FF loads, from Automatically Detected or No Proxy to Manual 127.0.0.1. In reading other articles I found the prefs.js file in my Profiles directory and deleted the two lines that reference a Proxy location as directed, as well as changed to the proxy.type setting to 0. Firefox is always closed when I do this. I reload FF and I'm right back to the Manual Proxy setting with the 127.0.0.1 address. The date/time stamp shows the prefs.js was edited at the same moment I reloaded FF, but obviously not by me, and the lines I deleted are right back in there.

These settings were fine forever. I got one of those fake anti-virus program scams on my system late last week, and this started happening then. However I've removed (or so I thought) all references to that program and it hasn't returned. Maybe a coincidence, maybe not.

Any help will be appreciated.

My proxy settings are being changed every time FF loads, from Automatically Detected or No Proxy to Manual 127.0.0.1. In reading other articles I found the prefs.js file in my Profiles directory and deleted the two lines that reference a Proxy location as directed, as well as changed to the proxy.type setting to 0. Firefox is always closed when I do this. I reload FF and I'm right back to the Manual Proxy setting with the 127.0.0.1 address. The date/time stamp shows the prefs.js was edited at the same moment I reloaded FF, but obviously not by me, and the lines I deleted are right back in there. These settings were fine forever. I got one of those fake anti-virus program scams on my system late last week, and this started happening then. However I've removed (or so I thought) all references to that program and it hasn't returned. Maybe a coincidence, maybe not. Any help will be appreciated.

All Replies (3)

the-edmeister
the-edmeister
  • Moderator
more options

See if you have a user.js file in your Profile folder.

http://kb.mozillazine.org/User.js_file

user.js is read after the prefs.js file is read, as Firefox is launched each time.

user.js is an optional file which doesn't come with Firefox, so "someone" added that file if it exists in your Profile. If you don't recall creating that file yourself, just delete it. Or if you did create that file and have a need for it, just edit out those two lines and save it.

S_Kinison
S_Kinison Umnini wombuzo
more options

I had looked for the user.js file and its nowhere to be seen in that directory (or anywhere else on my system--I checked just to be sure.)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).