Link with OIGateway problem (before ALERT 4.0 R1 B504):
Until the version of ALERT 4.0 R1 B519, the interfacing with an OI.GATEWAY OPC server through the ALERT Tunneler requires the use of the "Registry" option when adding the data server (chapter 4.1) in the interface of ALERT.
The "Registry" option can be activated through the radio button present in the "OPC server selection" window.