Read zenOn variables from Windows Service

[matteo.bernardon]

Good afternoon.
I want to read variables value from zenOn Runtime project using zenOn API.
I'm working with 7.60 SP 0 Build 36068 zenOn version.
If I use a simple C# Console Application everything works correctly.
I have an exception in the below function when I use a Windows Service:

IApplication _zApplication = Marshal.GetActiveObject("zenOn.Application") as Application;

Exception:
System.Runtime.InteropServices.COMException (0x80004005). Message: Operation unavailable (Exception from HRESULT: 0x800401E3 (MK_E_UNAVAILABLE))

Can someone help me?
Thanks!

Matteo