When you try to add a vcenter connection under “Hosting” tab in Studio, you get the below error sometimes:

Solution:

• Open your vcenter server in IE, like, https://vcenterServer.yourcompany.com.
• You will see certificate error. Click on “Continue to this Website (not recommended).
• Click on Certificate error in the address bar.
• Click View certificates and install the certificate.
• Make sure you install it to Local machine and select “Trusted People” in certificate store dialog box.
• After import is done, continue adding vcenter server in citrix studio.

You can also try steps given here: https://support.citrix.com/article/CTX138640