There is a known problem specifying arrays with Iconics DataSpy client (version 6.00.80.9) and the Kepware KepwareEX OPC server (version 4.70.200 -U). Sometimes adding items will fail, depending on the requested data type. For example, with the Simdemo.opf loaded on the server, monitoring an item ID of "Channel_1.Device_1.R0010[3]" fails if "VT_R8" datatype is selected. The inference of an array from the square brackets seems to contradict user selection of VT_R8 and the client fails to add, although no error is shown!

The only solution is to leave the default data type VT_EMPTY. This frequently works, but can also create items of previously selected Data Types instead. Sometimes when adding a non-array item, the result is an array of the previously requested type.

As the Kepware Quick Client (version 4.30.74 - U) appears to work correctly with the server, this would therefore appear to be a problem with the Iconics DataSpy client.