Dear professor,

I’ ve been struggling for a while already when running the attached model file.

The error message is the following:

“error: Impossible to find the steady state (the sum of square residuals of the static equations is 0.5097). Either the model doesn’t have a steady sta

te, there are an infinity of steady states, or the guess values are too far from the solution.”

Could you, please, help me to see what’s wrong?

Covid_19.mod (2.2 KB)