Error reading tag properties from remote tag provider

I have an Ignition 8.0.2 gateway and a connected Ignition 7.9.4 gateway. I am trying to read tag properties from the connected v7 gateway and getting a NullReferenceException when reading the HistoryProvider, historicalDeadbandStyle and a UDT property.

This is my code sample:

private static final BasicProperty<InterpolationMode> DeadbandStyleProperty =
        new BasicProperty<>("historicalDeadbandStyle", InterpolationMode.class,

private static final BasicProperty<Object> UdtProperty =
        new BasicProperty<>("My User Defined Type", Object.class);

List<String> properties = List.of(

String tagPath = "";

List<TagPath> propertyPaths =
        .map(p -> TagPathParser.parseSafe(String.format("%s.%s", tagPath, p)))

List<QualifiedValue> values = tagManager.readAsync(propertyPaths).get();

Any idea what I am doing wrong?

IIRC, there were bugs in cross-version remote tag provider functionality well into the v8.1 series. You probably need to upgrade.

{ Well, since you are using a development version that became end-of-life as soon as v8.1 was released, you need to upgrade anyways. }

Thank you. Upgrading to v8.1.23 seems to have fixed it

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