LOL prompts that the security certificate is invalid every time he logs in, because the system detects that the certificate failed authentication. The solution is as follows:

First, open IE browser, click Tools menu, and select Internet option;

Secondly, in the Internet options, select the Advanced tab;

3. Find the two options as shown in the Advanced tab, check them, and save the settings to exit IE.

Fourth, open the League of Legends, the problem is solved, the certificate is not available, and it no longer appears.