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Getting the error code: SEC_ERROR_UNKNOWN_ISSUER

  • 4 replies
  • 23 have this problem
  • 8 views
  • Last reply by dvinette

dvinette
dvinette

On yesterday I formatted my hard drive and ran a clean install of Windows 7 SP1 (64-bit). I installed firefox straight from the Mozilla website, and I get the crash reporter as soon as I open the program. I looked at some troubleshooting methods to see if I could get Firefox to open without crashing, but to no avail.

After a few hours I removed Firefox and every "Mozilla" folder on my computer, and I also ran cCleaner to remove the registry entries.

I then downloaded and installed the 64-bit version of Firefox (the install from the website installed the 32-bit version by-default). It opened just fine, but now I'm getting the SEC_ERROR_UNKNOWN_ISSUER error on some sites. Not all sites... but sites that I frequent such as google.com.

I've searched all over the internet for help and every "fix" that I find does not work. Here's a list of the things that I've done to try to resolve this:

- Uninstalled virus protection (TrendMicro), and tried a clean install of Firefox. I don't use Kasperky. - I checked my clock... date and time are correct. - Logged in using the "local admin" account. Gives the same error. - Opened Firefox in Safe Mode. Gives the same error. - I cleared/deleted my cache, and I also checked my proxy settings - Deleted the "cert8" file from my profile folder then restarted FF.

Again, I can get to many other sites, but can't get into anything that has to do with Google (Youtube, gmail, adwords, nothing) and a few other sites. I've tried pretty much every solution that I've seen online and nothing fixes this issue.

Please help.

Thanks,

DTV

On yesterday I formatted my hard drive and ran a clean install of Windows 7 SP1 (64-bit). I installed firefox straight from the Mozilla website, and I get the crash reporter as soon as I open the program. I looked at some troubleshooting methods to see if I could get Firefox to open without crashing, but to no avail. After a few hours I removed Firefox and every "Mozilla" folder on my computer, and I also ran cCleaner to remove the registry entries. I then downloaded and installed the 64-bit version of Firefox (the install from the website installed the 32-bit version by-default). It opened just fine, but now I'm getting the SEC_ERROR_UNKNOWN_ISSUER error on some sites. Not all sites... but sites that I frequent such as google.com. I've searched all over the internet for help and every "fix" that I find does not work. Here's a list of the things that I've done to try to resolve this: - Uninstalled virus protection (TrendMicro), and tried a clean install of Firefox. I don't use Kasperky. - I checked my clock... date and time are correct. - Logged in using the "local admin" account. Gives the same error. - Opened Firefox in Safe Mode. Gives the same error. - I cleared/deleted my cache, and I also checked my proxy settings - Deleted the "cert8" file from my profile folder then restarted FF. Again, I can get to many other sites, but can't get into anything that has to do with Google (Youtube, gmail, adwords, nothing) and a few other sites. I've tried pretty much every solution that I've seen online and nothing fixes this issue. Please help. Thanks, DTV

Chosen solution

Could you please include a screen capture of the error?

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All Replies (4)

alex_mayorga
alex_mayorga
  • Moderator

¡Hola!

Please see How to troubleshoot security error codes on secure websites.

Please let us know if this solves your question.

¡Gracias!

dvinette
dvinette Question owner

@alex_mayorga

Thanks for your response. I currently have no antivirus software installed. We use TrendMicro here at my job, but I uninstalled it to test Firefox and Google. Still can't access Google and other sites.

I'm using Windows 7 Professional, so I don't have the "Family Features" on this computer. Also I do not have Windows Essentials loaded. This is a clean install of Windows with not much on it.

Thanks again for your response, but this does not solve my problem.

DTV

alex_mayorga
alex_mayorga
  • Moderator

Chosen Solution

Could you please include a screen capture of the error?

dvinette
dvinette Question owner

I saved my profile folder before I formatted my hard drive. I copied the files from the old profile folder into the new one, and the error no longer appears. I thank everyone for your help.