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I am getting 'SEC_ERROR_UNKNOWN_ISSUER' trying to open certain sites running AVG and I do not experiance the same problems in other browsers.

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I run AVG internet security as my anti virus. The existing Mozilla support page does not indicate a solution for AVG anti-virus. The problem originated a couple of days ago and since then i have run multiple anti virus programs trying to rule out malware including running them while booted in safe mode. I primarily get the error when using the search function of the address bar and until now I could usually open google then search directly from google.com and get around the error. As of this question i can no longer reach google to use it as a work around. I do not experience any insecure connection problem when running google chrome or internet explorer. I have removed and re-downloaded both AVG and Firefox I have made sure my Firefox proxy setting is set to auto-detect proxy settings

I run AVG internet security as my anti virus. The existing Mozilla support page does not indicate a solution for AVG anti-virus. The problem originated a couple of days ago and since then i have run multiple anti virus programs trying to rule out malware including running them while booted in safe mode. I primarily get the error when using the search function of the address bar and until now I could usually open google then search directly from google.com and get around the error. As of this question i can no longer reach google to use it as a work around. I do not experience any insecure connection problem when running google chrome or internet explorer. I have removed and re-downloaded both AVG and Firefox I have made sure my Firefox proxy setting is set to auto-detect proxy settings

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I have attempted both an open DNS and have run each of the removal programs at least twice. I have begun trying to do the reset but when I attempt to reset i get a message stateing that the reset has failed. I then tried to do the reset through command prompts but when i enter the line 'software software.001' i am told that the file is in use by another process so the the reset still fails.

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System File Checker?

https://support.microsoft.com/en-us/kb/929833

Scroll just past that initial Windows 8.1 screenshot to get the steps for Windows 10.

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