In my model I had accidentally a variable which was getting as a value the steady state of an exogenous variable.
Of course this does not make any sense, but because I was trying various things in the model it happened.
Dynare does not give the particular error, it couldn’t even run the model. So it took my hours to understand what is going on.
Dynare was saying:
VariableNode::writeOutput: should not reach this point
Just as an idea I think it would be useful if you include it in the error messages.