ArcGIS Pro 2.5: “add tier” tool fails and end up with 999999 error,

[JamalNUMAN]

ArcGIS Pro 2.5: “add tier” utility network tool fails and end up with 999999 error,

I couldn’t figure out why “add tier” utility network tool fails and end up with 999999 error.

[JamalNUMAN]

The issue at the moment is that when perfuming the “set subnetwork definition”, I got nothing to add in the “subnetwork controllers”!

What could be the issue here?

[PaulLeBlanc1]

After assigning the terminal configuration to D1/1, you also need to assign the "Subnetwork Controller" Category.

[JamalNUMAN]

But how to assign "Subnetwork Controller" Category? Which tool do I need appy?

[PaulLeBlanc1]

Set Network Category—Utility Network Toolbox | Documentation 

I'd recommend you read Configure a utility network—ArcGIS Pro | Documentation 

[JamalNUMAN]

I'm revolving in the same circle of situation. Till now, I failed just to set a water device as reservoir (water source) to get the sample network (pipes) traced!