How to Fix Firefox Error sec_error_unknown_issuer?:
Mozilla Firefox Error SECERRORUNKNOWNISSUER FIX TutorialOn websites which are supposed to be secure (the URL begins with 'Firefox must verif. We had the same problem with a Comodo wildcard 'positive ssl' cert. We are running our website using a squid-reverse SSL proxy and Firefox would keep complaining 'secerrorunknownissuer' as you stated, yet every other browser was OK. I found that this is a problem of the certificate chain being incomplete. Download Mozilla Firefox, a free web browser. Firefox is created by a global not-for-profit dedicated to putting individuals in control online. Get Firefox for Windows, macOS, Linux, Android and iOS today!
Mozilla Fix Firefox error Premium onlinetech Support Company focuses on Firefox Error sec_error_unknown_issuer to avoid trouble due to our Mozilla Firefox. Sometimes users are using Mozilla Firefox to browse a website; you go to the website using an SSL certificate and receive an error that your connection is not secure. If you click to learn more, you will see the following message below.
Repair registry entries associated with error sec_error_unknown_issuer
If you see the error: SECERRORUNKNOWNISSUER in Firefox, then Firefox tries to connect to a website that is not configured properly and only accepts HTST (HTTP Strict Transport Security) connections. As a results it not possible to add an exception for this certificate. Clearing the browsing data will fix this. Clear the Browser Data on a Mac. Open Mozilla Firefox. Select the Menu button located in the top right corner of the window. Select Clear Recent History. For Time range to clear, select Everything. Then select Clear Now. Clear the Browser Data in Windows.
- Click on Start button
- Type “command” in the search box … do not hit it yet!
- With the CTRL-Shift on your keyboard, press ENTER
- You will be prompted with the permission dialog box.
- Click Yes
- A black box will open with the blinking cursor.
- Type “Regedit” and press enter
- In Registry Editor, select the error sec_error_unknown_issuer-related key (such as Firefox) that you want to back up
- From the File menu, select Export
- Follow Save to List, select the folder where you want to save the Firefox backup key.
- In the file name box, type a name for your backup file, such as “Firefox backup”.
- Export the range, make sure that “selected branch” is selected.
- Click Save
- The file is then saved with a .reg file extension.
- You now have a backup of the registry entry related to Firefox
Operate a complete malware scan of your PC:
Clear your system junk (temporary files and folders) with Disk Cleanup (
Cleanmgr)
Fix Firefox error sec_error_unknown_issuer (solution)
How to run Disk Cleanup (Windows XP, Vista, 7, 8, and 10):
- Click on Start button
- Type “command” in the search box … do not hit it yet!
- With the CTRL-Shift on your keyboard, press ENTER
- You will be prompted with the permission dialog box.
- Click Yes
- A black box will open with the blinking cursor.
- Type “cleanmgr” and press Enter
- Disk Cleanup You can start calculating how much captured disk space.
- Disk Cleanup dialog box will appear with a series of checkboxes you can select. In most cases, the “temporary files” category will occupy the most disk space.
- Check the boxes of categories that you want to clear and click OK.
Update your PC device driver:
Use Windows System Restore for “Undo” System Recently Recently
To use System Restore (Windows XP, Vista, 7, 8, and 10):
Sec_error_unknown_issuer Firefox Fix For Mac Catalina
- Click on Start button
- In the search box, type “System Restore” and press ENTER.
- In the results, click System Restore.
- Enter an administrator password (if prompted)
- Follow the wizard steps to select the restore point
- Restore your computer
- Uninstall and restore the Firefox program, connected to error sec_error_unknown_issuer
Uninstall and restore instructions for Windows 8, 10:
- To add the start menu image, place the cursor at the bottom of the screen
- Right-click to fetch the initial context menu
- Click Programs and Features
- Find out that the certificate is not trusted because the issuer certificate is an Anonymous-associated program under the Name column.
- Click on the Firefox-related entry
- Click Uninstall / Change on the top menu ribbon.
- Follow the on-screen instructions to uninstall your error sec_error_unknown_issuer-related program
- Uninstall your error sec_error_unknown_issuer-related program (such as Firefox), restore the program according to the Mozilla Foundation instructions.
Run Windows System File Checker (“SFC / scannow”)
System file tester is an easy tool that is included with Windows that allows you to scan and restore windows system files for corruption (including error-related sec_error_unknown_issuer)
- To run the system file checker (Windows XP, Vista, 7, 8, and 10):
- Click on Start button
- Type “command” in the search box … do not hit it yet!
- With the CTRL-Shift on your keyboard, press ENTER
- You will be prompted with the permission dialog box.
- Click Yes
- A black box will open with the blinking cursor.
- Type “Sfc / scannow” and press enter
- System file tester error will begin scanning for sec_error_unknown_issuer and other system file problems (Endurance – System scan may take for a while).
- Follow the on-screen commands
Install All Available Windows Updates:
Sec_error_unknown_issuer Firefox Fix Mac
Microsoft is constantly updating and improving Windows system files that may be related to error sec_error_unknown_issuer
To check for Windows updates (Windows XP, Vista, 7, 8 and 10):
- Click on Start button
- Type “update” in the search box and press enter.
- The Windows Update dialog box will appear.
- If updates are available, click the update button.
Perform a Clean Installation of Windows:
Reasons of Error sec_error_unknown_issuer:
- Corrupt download or incomplete installation of Firefox.
- Corruption in Windows registry from a recent Firefox-related software change
- Virus or malware infection that has corrupted Windows system files
- Program have maliciously or mistakenly deleted Firefox-related files.
