Fix: sec_error_unknown_issuer on Safari

The error “Uses an invalid security certificate. The certificate is not trusted, because the issuer Certificate is Unknown (Error Code : sec_error_unknown_issuer)” followed by a request to call  0-800-112-0034 is a fake warning, generated by a adware on your browser/system which prevents you from accessing the internet. What these guys wants you to do is call the company; so that they can trick you into believing them that’s this was a virus and steal your money.

This is a new type of tech support scam. In this guide; i will list down the steps you can take to fix this issue.


First Force Quit Safari

  1. Press command + option + esc keys together at the same time. Wait.
  2. When Force Quit window appears, select  Safari if not already.
  3. Press Force Quit button at the bottom of the window.   Wait.
  4. Safari will quit.
  5.  Relaunch Safari holding the shift key down.
  6. Click  Safari > Preferences > Security > Privacy and choose  Cookies and website data,  Click “Details” button. Remove the cookie related to this, if there is one.
Kevin Arrows
Kevin is a dynamic and self-motivated information technology professional, with a Thorough knowledge of all facets pertaining to network infrastructure design, implementation and administration. Superior record of delivering simultaneous large-scale mission critical projects on time and under budget.

Expert Tip

Fix: sec_error_unknown_issuer on Safari

If the issue is with your Computer or a Laptop you should try using Restoro which can scan the repositories and replace corrupt and missing files. This works in most cases, where the issue is originated due to a system corruption. You can download Restoro by clicking the Download button below.

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