800xA Property Transfer from Controller to OPC

Hi,

I want to do a proprety transfer from the controller to OPC (third-party Kepware Server v5). As you can see in the attach I am pointing to the Real Pca-Value and the path is correct but is it not working. If I am wrriting from Grafic Element PG2 then I am getting the value in the other end. The Property Transfer service is working fine because I am using it to get something in the controller from IEC. I am getting also and sporadic error that the property transfer cannot write into. Dose anyone knows where is the problem or if I can do this in another way? Thank you!