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Why is everything from Mozilla getting blocked?

  • 14 replies
  • 1 has this problem
  • 1 view
  • Last reply by erlisd

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I did a clean install of firefox (after removing it completely), and now I'm having trouble installing any addon or accessing any of the mozilla's websites. Actually websites open, but do not load properly. Only the text gets downloaded. This happens with anything that has the domain mozilla.org or related pages. To get a better idea what is happening, take a look at the screenshot I've attached. Also something else to notice... All of the mozilla websites get loaded properly on other browsers, so I'm assuming this is something related to firefox. And by the way, I've tried refreshing firefox, or going in safe mode, trying from a private window, or deleting the profile folder. So where could the problem be?

UPDATE: I restored the old profile folder, and everything seems to work fine. After deleting it again, the problem is again. I tested some other websites, and it and only one of them had certificate problems as Mozilla. I think that firefox creates a corrupted profile folder.

I did a clean install of firefox (after removing it completely), and now I'm having trouble installing any addon or accessing any of the mozilla's websites. Actually websites open, but do not load properly. Only the text gets downloaded. This happens with anything that has the domain mozilla.org or related pages. To get a better idea what is happening, take a look at the screenshot I've attached. Also something else to notice... All of the mozilla websites get loaded properly on other browsers, so I'm assuming this is something related to firefox. And by the way, I've tried refreshing firefox, or going in safe mode, trying from a private window, or deleting the profile folder. So where could the problem be? UPDATE: I restored the old profile folder, and everything seems to work fine. After deleting it again, the problem is again. I tested some other websites, and it and only one of them had certificate problems as Mozilla. I think that firefox creates a corrupted profile folder.
Attached screenshots

Modified by erlisd

Chosen solution

erlisd said

@James I use ESET Smart Security. But as mentioned, this does not happen if I use the old user profile, but if I create a new one.

Perhaps because the new profile has a default cert8.db that doesn't have the ESET signing certificate trusted as an authority to issue the fake certificates ESET presents to Firefox when filtering SSL connections?

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All Replies (14)

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hi, please make sure that your system clock is set to the right date, time & timezone: time.is

in addition, since there are currently some issues downloading extensions directly from the "get addons" panel within the firefox addons manager, please try downloading them from https://addons.mozilla.org/ instead.

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philipp said

hi, please make sure that your system clock is set to the right date, time & timezone: time.is in addition, since there are currently some issues downloading extensions directly from the "get addons" panel within the firefox addons manager, please try downloading them from https://addons.mozilla.org/ instead.


As mentioned on the update, the old profile folder make firefox work. The time could be off by some milliseconds. And also I mentioned the any mozilla domain does not open properly.

Modified by erlisd

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what happens if you try to load the following url: https://addons.cdn.mozilla.net/static/img/app-icons/med/firefox.png any particular error message/error code?

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I get an untrusted connection... I think I should post it as a bug on bugzilla.

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Posts crossed... I can't tell what page that is. If it is the "Get Add-ons" section of the Add-ons page, there may be a special issue with that one.

Modified by jscher2000 - Support Volunteer

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erlisd said

I get an untrusted connection... I think I should post it as a bug on bugzilla.

Could you expand the Technical Details section and copy/paste what you find there into a reply.

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What antivirus do you have as some do interfere with secure connections like say with Avast with it's https feature.

Modified by James

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Here: addons.cdn.mozilla.net uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. (Error code: sec_error_unknown_issuer)

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@James I use ESET Smart Security. But as mentioned, this does not happen if I use the old user profile, but if I create a new one.

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Chosen Solution

erlisd said

@James I use ESET Smart Security. But as mentioned, this does not happen if I use the old user profile, but if I create a new one.

Perhaps because the new profile has a default cert8.db that doesn't have the ESET signing certificate trusted as an authority to issue the fake certificates ESET presents to Firefox when filtering SSL connections?

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It could be. The old profile maybe has more than a year that has been created I think. Still, after replacing the new profile with the old one (manually), doesn't the cert8.db get modified? Anyway, what could be different for eset for the old and new database?

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I can't keep track of the steps for all these different security products!

Ideally, ESET would detect your Firefox and insert the certificate into the new profile automatically. But you might need to trigger it in some way.

I looked these up earlier this year, and they might be obsolete by now, but in case they're useful:

EndPointSecurity 6: http://download.eset.com/manuals/eset_ees_6_userguide_enu.pdf (section 3.8.3.1.4)

EndPoint Antivirus 6: http://download.eset.com/manuals/eset_eea_6_userguide_enu.pdf (section 3.8.2.1.4)

NOD32 Antivirus 8: http://download.eset.com/manuals/eset_eav_8_userguide_enu.pdf (section 4.2.3.4.1)

Smart Security 8: http://download.eset.com/manuals/eset_ess_8_userguide_enu.pdf (section 4.3.3.4.1)

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After disabling and re-enabling the SSL filtering, everything seems to work fine. I'm not quite sure that this was related (maybe ESET's database was updated), but whats important is that everything works fine now.