nginx install error

[wangyiran125]

i want to install nginx plus .and i try these steps step by step
Setup instruction for RHEL6/CentOS6/Oracle Linux 6
Create /etc/ssl/nginx/ directory
Move CA.crt, nginx-repo.key and nginx-repo.crt files to /etc/ssl/nginx/
directory
Copy nginx-plus-6.repo file to /etc/yum.repos.d/ directory
Run yum install nginx-plus to install nginx-plus package. Please keep in
mind that old nginx package (if any) will be replaced.
In order to upgrade from the previous version of nginx-plus, run yum upgrade
nginx-plus

but when i type yum install nginx-plus,it report
Repo nginx-plus forced skip_if_unavailable=True due to:
/etc/ssl/nginx/nginx-repo.crt
Repo nginx-plus forced skip_if_unavailable=True due to:
/etc/ssl/nginx/nginx-repo.key
https://plus-pkgs.nginx.com/centos/6/x86_64/repodata/repomd.xml: [Errno 14]
PYCURL ERROR 22 - "NSS: client certificate not found:
/etc/ssl/nginx/nginx-repo.crt"
Trying other mirror.
Setting up Install Process
No package nginx-plus available.
Error: Nothing to do

how to solve it?

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,262587,262587#msg-262587