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SEC_ERROR_UNKNOWN_ISSUER and AVG

  • 4 replies
  • 1 has this problem
  • 4 views
  • Last reply by FredMcD

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I am also having the SEC_ERROR_UNKNOWN_ISSUER problem where web browsing is impossible. However, when I tried to research the troubleshooting article with anti-virus programs being one probable cause (https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER ), the article did not have a mention for AVG, the anti-virus program I use. One time, I tried clearing my web browsing and cookie history to see if it would fix it, but to no avail. Did a virus scan - that didn't work. Followed by the Adware Cleaner - that too was a failure.

The only way I was able to fix this problem... was to restart my computer.

I am also having the SEC_ERROR_UNKNOWN_ISSUER problem where web browsing is impossible. However, when I tried to research the troubleshooting article with anti-virus programs being one probable cause (https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER ), the article did not have a mention for AVG, the anti-virus program I use. One time, I tried clearing my web browsing and cookie history to see if it would fix it, but to no avail. Did a virus scan - that didn't work. Followed by the Adware Cleaner - that too was a failure. The only way I was able to fix this problem... was to restart my computer.

Modified by no1wammy

All Replies (4)

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Hi no1wammy, sorry the article hasn't been updated yet, but AVG now works like Avast and you could use the advice for Avast (perhaps not exactly).

The only way I was able to fix this problem... was to restart my computer.

That's a good strategy!

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Eh, best the article be updated to include AVG, just in case. While instructions may be the same, name conventions could be different. Better safe than sorry.

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Hi, yes someone will get to that...would you care to ?

AVG is no owned by Avast so please visit both Community forums for work arounds, see what others are doing etc...

Restarting your computer is actually a must do and should be done on a daily basis.

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Separate Security Issue: Update your Flash Player or remove it using these links; http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html Uninstall Flash Player | Windows http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-mac-os.html Uninstall Flash Player | Mac

Note: Windows users should download the ActiveX for Internet Explorer. and the plugin for Plugin-based browsers (like Firefox).

Note: Windows 8 and Windows 10 have built-in flash players and Adobe will cause a conflict. Install the plugin only. Not the ActiveX.

Flash Player Version: Version 29.0.0.171

https://get.adobe.com/flashplayer/ Direct link scans current system and browser Note: Other software is offered in the download. <Windows Only>

https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, Win IE . . . .) Note: Other software is offered in the download. <Windows Only> +++++++++++++++++++ See if there are updates for your graphics drivers https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration