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Cannot access Youtube anymore (sec_error_unknown_issuer)

  • 6 replies
  • 8 have this problem
  • 26 views
  • Last reply by Phoxuponyou

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Dear Mozilla support,

since a few weeks now I have a strange problem with Firefox on my Windows 7 machine: When trying to open Youtube and often when trying to open Google (and any google related sites such as google docs) it shows me the error "sec_error_unknown_issuer" - a bad certificate. I have already tried a few things like following the advice in the "how to troubleshoot sec_error_unknown_issuer" guide, however nothing has worked so far. I have also made sure that my PC time is correct. The issued certificate is by "BullGuard SSL Proxy CA". I have checked in this direction and found a Bullguard forum thread with a similar issue suggesting a run command that apparently resets or renews the certificates but it has not changed anything. Furthermore, an antivirus scan with Malwarebytes and Bullguard has found nothing. Launching Firefox in safe mode did not prevent the problem. Youtube and Google work fine in Internet Explorer.

The first time I got this problem I have tried to do a windows restore point to the last update where I was sure the problem was not yet present. However this resulted in my windows user account becoming corrupted so I had to create a new one. The problem seemed solved for a few days until it reoccurred. I cannot think of anything else to do now. You are my last hope. Thank you for reading.

Dear Mozilla support, since a few weeks now I have a strange problem with Firefox on my Windows 7 machine: When trying to open Youtube and often when trying to open Google (and any google related sites such as google docs) it shows me the error "sec_error_unknown_issuer" - a bad certificate. I have already tried a few things like following the advice in the "how to troubleshoot sec_error_unknown_issuer" guide, however nothing has worked so far. I have also made sure that my PC time is correct. The issued certificate is by "BullGuard SSL Proxy CA". I have checked in this direction and found a Bullguard forum thread with a similar issue suggesting a run command that apparently resets or renews the certificates but it has not changed anything. Furthermore, an antivirus scan with Malwarebytes and Bullguard has found nothing. Launching Firefox in safe mode did not prevent the problem. Youtube and Google work fine in Internet Explorer. The first time I got this problem I have tried to do a windows restore point to the last update where I was sure the problem was not yet present. However this resulted in my windows user account becoming corrupted so I had to create a new one. The problem seemed solved for a few days until it reoccurred. I cannot think of anything else to do now. You are my last hope. Thank you for reading.

Chosen solution

For some reason, Bullguard support has been suggesting to Firefox users to use the Refresh feature to address this problem (according to replies in threads in the past couple weeks). That's rather drastic, as you can see from this article: Refresh Firefox - reset add-ons and settings.

Could you do this three-minute experiment -- the idea is if Bullguard can insert its certificate into a new profile, then we could copy the certificate file (cert8.db) from the new profile back to your regular one:

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox and start up in the Profile Manager using Start > search box (or Run):

firefox.exe -P

Don't delete anything here!

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like TEST2016, and skip the option to relocate the profile folder. After creating the profile, select it and start Firefox in that profile.

Can you get to Google sites?

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

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Hey there, sounds like a basic problem.

It seems your AV solution, Bullguard, is intercepting secure traffic and pushing it out again under its own certificate. It's basically a man-in-the-middle attack: the certificate does not match as it should after Bullguard highjacks the data.

This can probably be remedied by introducing the Bullguard certificate in Firefox (so Firefox knows to trust it), or by turning off SSL/HTTPS scanning in Bullguard to stop the data traffic highjacking. I have no expertise with Bullguard, so you'll have to dig around or wait for someone who knows about Bullguard.

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Chosen Solution

For some reason, Bullguard support has been suggesting to Firefox users to use the Refresh feature to address this problem (according to replies in threads in the past couple weeks). That's rather drastic, as you can see from this article: Refresh Firefox - reset add-ons and settings.

Could you do this three-minute experiment -- the idea is if Bullguard can insert its certificate into a new profile, then we could copy the certificate file (cert8.db) from the new profile back to your regular one:

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox and start up in the Profile Manager using Start > search box (or Run):

firefox.exe -P

Don't delete anything here!

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like TEST2016, and skip the option to relocate the profile folder. After creating the profile, select it and start Firefox in that profile.

Can you get to Google sites?

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

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One other thought: If you exit out of Firefox completely and re-run the Bullguard program installer, it may as part of installation insert itself into all the Firefox cert8.db files it can find. Not sure that will work (or stick) but if it does, you could make a backup of that file for future use.

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You can also export the Bullguard certificate if you see it in the certificate manager once you have placed the cert8.db file in the profile folder. The certificate should appear under the Authorities tab.

  • Tools > Options > Advanced > Certificates: View Certificates
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Huzzah! jscher2000, your idea with the cert8.db file worked perfectly. Thanks a ton man! I was starting to think this is caused by a really evil undetectable virus but apparently really just the certificate problem. Hopefully it will stay working now.

And of course thanks to everyone else who spent their thought energy on my problem. ;)

Modified by Baryonyx

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Glad you got it solved; I hear ESET has a separate button to reintroduce the certification, guess Bullguard, Bitdefender etc. have to rely on re-running the installer.