Solution to Win7 system security certificate expiration

　 1, press win+r key, open run, enter "MMC", click OK;

　　2, select "File" in the console window--"Add or remove management";

　　3, in the Management Unit box select "Certificate", click Add;

　　4, in the certificate Management unit of the account select "My user account", click "Finish";

　　5, expand the "certificate-Current User"--"Trusted Root certification Authority"-"certificate", to find the certificate you need to delete, right-click Select Delete;

　　6. Reopen the website that requires the certificate, click "View Certificate"-"Install to Trusted Root certification authority".