Every time I opened Firefox it was setting itself to a local proxy server and hence I could not get out to the internet. This had been driving me crazy for days and today I finally got to the bottom of it.firefox_

Does your Firefox keep setting itself to a manual proxy? Read on to see what caused it for me and how to fix it.

I installed a new version of Fiddler a week or so ago and/or a Fiddler Hook Extension for Firefox. It turns out that one of these was the culprit.

I did some Googling and Binging on the matter and was directed to update the network.proxy.type setting in about:config through the Firefox shell as shown below:


Unfortunately this didn’t fix the issue as it continued to set itself back to the manual proxy. However, it got my noodle thinking that something had to be executing to keep setting it back and so I checked out my add-ons.

As soon as I saw the Fiddler Hook I figured this must be the problem and lo and behold it was. Disabling the Fiddler Hook as shown below fixed the problem.

Fiddler Hook Extension

That was a huge relief as I thought it might be a virus.