Thanks.
Already saw this guide, unfortunately it didn't help.
The only relevant paragraph which relates to my case is the following:
"
- The AppDynamics SaaS Controller uses certificates signed by DigiCert. In some cases, SaaS customers must import the DigiCert root certificates into the Windows Trusted Root Certification Authorities store.
"
There's no explanation regarding how to do so, and besides, I have 3 DigiCert certificates in the Trusted Root Certification Authorities list:
DigiCert Assured ID Root CA
DigiCert Global Root CA
DigiCert High Assurance EV Root CA
Using Windows 8.1 Enterprise.