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An Information box will appear as shown below, click OK. Basically, FLUENT switches the discretization scheme for momentum equation to Bounded Central-Differencing. It also urges to change the order to Second Order in the Order Implicit for Transient Formulation in the Solution Methods which , which we will do in the later stages. 
For incompressible flows, the energy is decoupled from the continuity and the momentum equations. So the energy equation is not solved. Make sure that Energy is set to Off in Problem Setup > Models > Energy.