Hi,
I had the same problem. Finaly i had to go to: System > trust > Authorities and import my CA Certificates from external CA (root + Intermediate). You can import them without private keys. After that you can go to: System > trust > Certificates and import your singned Server Request.
I had the same problem. Finaly i had to go to: System > trust > Authorities and import my CA Certificates from external CA (root + Intermediate). You can import them without private keys. After that you can go to: System > trust > Certificates and import your singned Server Request.