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Can't connect to sync due to certificate error.

  • 4 replies
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  • 7 views
  • Last reply by maurg

maurg
maurg
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I cannot connect to FF sync, either sign in or sign up, from computer connected to my home router. But I was able to 6 months ago. I only noticed now because I upgraded my PC and tried to sign in to sync to get FF up to speed.

If I look at the Developer console -> Networking tab while trying to sign in, I see that the error is during a request to "https://api.accounts.firefox.com/". Attempting to access the API url from the browser shows a certificate error with the code MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE.

I tested from multiple computers connected to the same network and the same error always occurs.

On the other hand, connecting one of those computers straight to the ISP modem makes Sync work again. Both the ISP modem and the router (Asus RT-56NU) have firewalls disabled and I tested DMZ'ing one of the computers to no avail. Another information, the "about:sync-log" page is blank. It seems this error does not register there. Starting FF in safe mode did not work, neither did a clean install.

I'm at my wits end and I did not find any solutions in the forum.

Thank you

I cannot connect to FF sync, either sign in or sign up, from computer connected to my home router. But I was able to 6 months ago. I only noticed now because I upgraded my PC and tried to sign in to sync to get FF up to speed. If I look at the Developer console -> Networking tab while trying to sign in, I see that the error is during a request to "https://api.accounts.firefox.com/". Attempting to access the API url from the browser shows a certificate error with the code MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE. I tested from multiple computers connected to the same network and the same error always occurs. On the other hand, connecting one of those computers straight to the ISP modem makes Sync work again. Both the ISP modem and the router (Asus RT-56NU) have firewalls disabled and I tested DMZ'ing one of the computers to no avail. Another information, the "about:sync-log" page is blank. It seems this error does not register there. Starting FF in safe mode did not work, neither did a clean install. I'm at my wits end and I did not find any solutions in the forum. Thank you

Chosen solution

Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

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All Replies (4)

philipp
philipp
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hi maurg, do you get more information when you click on the MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE error code? if so, please copy that to the clipboard and paste it here into a reply on the forum. thank you!

maurg
maurg Question owner
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Sorry for the delay in responding, I was not home.

The error code is non-clickable as can be seen on the attached image. The only part of the page that is clickable is the "Learn more..." link which redirects to "https://support.mozilla.org/en-US/kb/what-does-your-connection-is-not-secure-mean"

Attached as image both the network tab on the developers console and the error message.

Thanks!

cor-el
cor-el
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Chosen Solution

Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

maurg
maurg Question owner
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Weirdly enough, after rebooting windows 10 in safe mode sync started working even on normal windows startup.

Thanks for the help.