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Jackie Gable
Jackie Gable
1,539 Points

"Certificate Error" warning and "This site is not secure"

After installing server, when opening localhost web pages I receive this message "CERTIFICATE ERROR" and "This Site is not secure" and "Your PC doesnt trust this website's security certificate" and "Error Code: DLG_FLAGS_INVALID_CA".

How can I fix this problem? When Googling this issue some have suggested disabling UAC or buying a security certificate. There was nothing in your video or notes about installing a security certificate so Im not sure how to proceed. Hope you can help. Thanks in advance.

1 Answer

As this is a pretty old post, would I be correct in assuming you're not still waiting for an answer?

Disabling UAC would have no effect on this issue.

Buying a security certificate could fix this issue - however it is not the only solution that would.

It would also be possible to configure your computer to generate and valid self-signed certificate.

Alternatively you could use LetsEncrypt to generate a trusted third-party certificate - although that does have some additional prerequisites.

If this is still an issue for you, and you would like some assistance, could I ask you to confirm which operating system you are using (I am assuming some version of Windows after Vista as you mentioned UAC) and which web server software you are using (I would assume the version of IIS that ships with your version of Windows).