Simulink Problem: Derivative input is Inf or NaN

I face the following Simulink problem at the input of the integration block:

Derivative input -14 of 'process_model4/unit1/Integrator' at time 0.0 is Inf or NaN. Stopping simulation. There may be a singularity in the solution. If not, try reducing the step size (either by reducing the fixed step size or by tightening the error tolerances)

This is happening even after I've deleted the input argument 14 and the blocks associated with it. And now there's no such variable as Derivative input 14. I tried changing the ode solver, but still the error persists. How do I deal with it? Please help. I'd appreciate step by step instructions.