Local development and testing interfaces can refund, but this time with the server or machine iis to call would prompt "connection was closed unexpectedly."
1. Business Center to generate and download the certificate.
2. The certificate on a local disk folder.
3. Double-click the certificate (.p12) file, select the local computer, the password for the merchant code, all the certificates in person.
4. Call Interface added in a certificate request
5. iis provided to configure the certificate, with reference to: https: //www.cnblogs.com/xiaoxiangpaou/p/9799527.html