Thank you for your response.
I progressed a bit more. I could connect KVM from remote host in my local network, but not with local host.
As management tool I used VCN real plus and Manageability Commander Tool.
In Local host cases I encounter with the errors above.
In Remote host cases, I could connect with VCN plus but not with Manageability Commander Tool, so i could not still gain SOL access.
Connecting to AMT locally allows you to gather information, and change certain settings. However, like KVM most vPro functionality requires a remote connection. You can not KVM into your own local computer.
There seems to be a bug with the latest version of the Manageability Commander Tool. Try adding your vPro computer again, but this time use the built in admin digest account. Changing to the digest account should allow you to establish a SOL connection. Another option is to use the Intel vPro Platform Solution Manager. https://downloadcenter.intel.com/Detail_Desc.aspx?DwnldID=22183