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 Googl… (閱讀更多)
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.