NetDDE is not supported for InTouchView applications.
By design, an InTouchView application does not serve data to any other source, including
InTouch HMI itself. When WindowViewer starts, it verifies if the application is an
InTouchView application. When WindowViewer detects an InTouchView application, it
does not register to become a DDE server. Industrial Graphics make use of the client
layer when accessing InTouch tags, and appear as a third-party client trying to access
WindowViewer as a data server. As a result, Industrial Graphics cannot communicate
with InTouch tags when used with an InTouchView license.
In Industrial Graphics, InTouch:<tagname> is still a valid method of referring to an InTouch tag on a local node.