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

This thread was archived. Please ask a new question if you need help.

SSL connection fails before browsing to a non-SSL site when using a proxy

  • 1 reply
  • 2 have this problem
  • 11 views
  • Last reply by Tonnes

FMX1
FMX1
more options

This is the same problem as https://support.mozilla.org/en-US/questions/1142423 but I now have a much clearer description of it.

Firefox 49.0.2 running on Windows 7, all extensions disabled. I've cleared all history (cache, site preferences, etc.) I have an HTTP proxy configured (Manual Proxy Configuration, "Use this proxy server for all protocols" checked).

If I browse to an HTTPS site after starting Firefox before browsing to an HTTP (non-SSL) site the status bar quickly changes between "Looking up (host)...", "Connecting to (host)..." and "Waiting for (host)..." several times and then shows the "Secure Connection Failed" page, as in the screenshot on https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

This happens on every HTTPS site I try, e.g. https://support.mozilla.org/, https://www.google.com/, https://www.pandora.com/, https://www.ycombinator.com/ (note that this last one does not use HSTS).

My proxy server requires HTTP authentication and Firefox does not even prompt for a username and password at this point. I control the proxy server and can see in its logs that there are no connection attempts yet.

If I browse to an HTTP site and enter the proxy credential when prompted I can then browse to HTTPS sites as normal. It doesn't have to be the same site, e.g. I can browse to http://www.yahoo.com/ and then https://www.microsoft.com/ will work. However, if I cancel the proxy credentials prompt the issue continues. It takes a successful HTTP connection to make HTTPS work.

This is the same problem as https://support.mozilla.org/en-US/questions/1142423 but I now have a much clearer description of it. Firefox 49.0.2 running on Windows 7, all extensions disabled. I've cleared all history (cache, site preferences, etc.) I have an HTTP proxy configured (Manual Proxy Configuration, "Use this proxy server for all protocols" checked). If I browse to an HTTPS site after starting Firefox before browsing to an HTTP (non-SSL) site the status bar quickly changes between "Looking up (host)...", "Connecting to (host)..." and "Waiting for (host)..." several times and then shows the "Secure Connection Failed" page, as in the screenshot on https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message This happens on every HTTPS site I try, e.g. https://support.mozilla.org/, https://www.google.com/, https://www.pandora.com/, https://www.ycombinator.com/ (note that this last one does not use HSTS). My proxy server requires HTTP authentication and Firefox does not even prompt for a username and password at this point. I control the proxy server and can see in its logs that there are no connection attempts yet. If I browse to an HTTP site and enter the proxy credential when prompted I can then browse to HTTPS sites as normal. It doesn't have to be the same site, e.g. I can browse to http://www.yahoo.com/ and then https://www.microsoft.com/ will work. However, if I cancel the proxy credentials prompt the issue continues. It takes a successful HTTP connection to make HTTPS work.

All Replies (1)

Tonnes
Tonnes
  • Locale Leader
more options

Would you mind following up in your original question?

Additionally, you could try the solution mentioned in this question.