Download your SSL Certificate & its Intermediate CA certificate from here

Step 1: Importing your Intermediate CA certificate:

1. Open the Juniper admin console.
2. Under System > Configuration > Certificates > Device Certificates. Click Intermediate Device CAs.
   
   

3. Click Import CA Certificate
   
   
   
   
4. Browse to the location and path of your saved Intermediate CA certificate file.
   
   
   
   
5. You should see a message confirming that the certificate has been imported successfully. Click Done.

Step 2: Importing your SSL certificate:

1. Under System > Configuration > Certificates > Device Certificates.
2. Click on Pending CSR.
   
   
   
   

3. Under Import signed certificate, Click browse and specify the location and file path of your SSL certificate and then click Import.
   
   
   
   
4. You should see a message confirming that the certificate has been imported successfully. The Server Certificate should appear in the list of Device Certificates.