1. For example, 12306 "There is something wrong with the safety certificate of this website" appears on the railway ticketing website, as shown in the following figure.

2. The address bar of the website still appears, and the certificate is wrong. Click on the untrusted certificate.

3. Return to the homepage to download the root certificate.

4. Decompress after downloading and prepare for installation.

5. Double-click to open the installation root certificate.

6. Follow the prompts to install the certificate to a trusted storage location, as shown in the figure.

7, continue to the next step, finally completed, pop-up warning, choose Yes,

8. After the installation is completed, you will be prompted to import successfully. Restart the browser and open the website again, and the problem is solved perfectly.