[This is one of a series of example entries which you might create on your own intranet site, in order to help your users use EA better. This page will be called by the built-in help of some Model Expert example reference models.]
{This is one of the built-in checks which Model Expert performs on your models}
You have tried to create a connection between two elements, but the kind of connection you have chosen isn’t defined in your Model Expert Reference Model.
You will see this when you are working in a Managed Package, where that package is using a Reference Model which says what kinds of elements can exist in it, and what kinds of connections are allowed between them.
One of the great strengths of EA is that you can create almost any kind of connection between almost any kinds of element. But connections mean something, so when we’re modelling, we need to take care to be consistent in which kinds of connector we use.
A Model Expert Reference Model lets you define exactly which kinds of connector you will allow between which kinds of element, so that your models are simpler and clearer.