Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

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.

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

After FF has been running for a while (hours/days), I start getting the error "firefox is configured to use a proxy server that can't be found"

  • 1 reply
  • 1 has this problem
  • 8 views
  • Last reply by guigs

more options

After FF has been running for a while (hours/days), I start getting the error "firefox is configured to use a proxy server that can't be found"

I'm using a 'manual' proxy. When this happens, I can still resolve the hostname of the proxy (using nslookup) and can ping it by hostname with a response. Other browsers continue to use the same proxy successfully.

Changing the proxy hostname to another proxy doesn't resolve the problem--I continue to get the same error. Changing to a proxypac file or changing to use system settings (same proxy.pac URL) also don't resolve the issue.

I've not tried putting the proxy's IP instead of hostname in the config dialog.

After FF has been running for a while (hours/days), I start getting the error "firefox is configured to use a proxy server that can't be found" I'm using a 'manual' proxy. When this happens, I can still resolve the hostname of the proxy (using nslookup) and can ping it by hostname with a response. Other browsers continue to use the same proxy successfully. Changing the proxy hostname to another proxy doesn't resolve the problem--I continue to get the same error. Changing to a proxypac file or changing to use system settings (same proxy.pac URL) also don't resolve the issue. I've not tried putting the proxy's IP instead of hostname in the config dialog.

All Replies (1)

more options

Hi htroberts,

Try that :-)

proxy's IP instead of hostname in the config dialog.

Ideally though you should have the Proxy set to use the computer's configuration.

Firefox -> Preferences -> Options -> Advanced -> Network -> Connection -> Settings

If the preferences are reverting to another http://kb.mozillazine.org/Preferences_not_saved