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Access Denied Error 21 message

  • 1 reply
  • 1 has this problem
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  • Last reply by Terry

kentuckywoman2
kentuckywoman2
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I have a subscription to ancestry.com. However, I've noticed several Firefox updates ago that I can no longer write a story and add it to an ancestor's media gallery. When I do, I keep getting this:

Access Denied Error 21

What happened? This request was blocked by security rules.

Your IP: (gives my IP addy) Incident ID: (gives a different incident ID each time I try it and get the error message).


WHAT IS this? And how can I resolve it? I have completely deleted my browser history, cookies, cache, everything and it doesn't make a difference. I'm still getting this message but ONLY in Firefox. Not in other browsers. I use Firefox to do most of my genealogical research, but this may have to change if I can't get it to work with ancestry.com. I've also alerted them to the problem, but so far they haven't come up with a solution, other than to delete cookies/cache/history, which I have done. It can't be my computer or it would do it on all three browsers I have installed - Microsoft Edge, Google Chrome, and Mozilla Firefox. But it doesn't. Only in Firefox. It has to be something in the browser settings. Anyone have a clue?

I have a subscription to ancestry.com. However, I've noticed several Firefox updates ago that I can no longer write a story and add it to an ancestor's media gallery. When I do, I keep getting this: Access Denied Error 21 What happened? This request was blocked by security rules. Your IP: (gives my IP addy) Incident ID: (gives a different incident ID each time I try it and get the error message). WHAT IS this? And how can I resolve it? I have completely deleted my browser history, cookies, cache, everything and it doesn't make a difference. I'm still getting this message but ONLY in Firefox. Not in other browsers. I use Firefox to do most of my genealogical research, but this may have to change if I can't get it to work with ancestry.com. I've also alerted them to the problem, but so far they haven't come up with a solution, other than to delete cookies/cache/history, which I have done. It can't be my computer or it would do it on all three browsers I have installed - Microsoft Edge, Google Chrome, and Mozilla Firefox. But it doesn't. Only in Firefox. It has to be something in the browser settings. Anyone have a clue?

All Replies (2)

Terry
Terry
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According to an answer I found in Microsoft answers, you can try changing your DNS settings in Control Panel. The recommended settings are the Google ones, 8.8.8.8 and 8.8.4.4.

Your Firefox is probably set to use CloudFare (see Settings > General > Network Settings) so, before changing anything else, I would try making exceptions of ancestry.com and any related sites by adding them to the following preference in about:config. network.trr.builtin-excluded-domains

WARNING: Changing preferences through this interface not officially supported Hidden settings edited using the about:config tool are explicitly not supported, which means that Mozilla makes no guarantees they will be supported in the future, or that Mozilla will fix them if they break. Mozilla does not test these preferences, and will not in the future. That includes security and performance testing which these preferences may affect.

[Warning added by moderator]

https://support.mozilla.org/kb/firefox-dns-over-https https://support.mozilla.org/en-US/kb/dns-over-https-doh-faqs https://wiki.mozilla.org/Trusted_Recursive_Resolver#DNS-over-HTTPS_Prefs_in_Firefox

https://support.mozilla.org/en-US/kb/about-config-editor-firefox

Modified by Chris Ilias

Terry
Terry
more options

According to an answer I found in Microsoft answers, you can try changing your DNS settings in Control Panel. The recommended settings are the Google ones, 8.8.8.8 and 8.8.4.4.

Your Firefox is probably set to use CloudFare (see Settings > General > Network Settings) so, before changing anything else, I would try making exceptions of ancestry. com and any related sites by adding them to the following preference in about:config. network.trr.builtin-excluded-domains

WARNING: Changing preferences through this interface not officially supported Hidden settings edited using the about:config tool are explicitly not supported, which means that Mozilla makes no guarantees they will be supported in the future, or that Mozilla will fix them if they break. Mozilla does not test these preferences, and will not in the future. That includes security and performance testing which these preferences may affect.

[Warning added by moderator]

https://support.mozilla.org/kb/firefox-dns-over-https https://support.mozilla.org/en-US/kb/dns-over-https-doh-faqs https://wiki.mozilla.org/Trusted_Recursive_Resolver#DNS-over-HTTPS_Prefs_in_Firefox

https://support.mozilla.org/en-US/kb/about-config-editor-firefox

Modified by Chris Ilias