The error message Quanew optimization cannot be completed indicates that the optimization algorithm was not able to properly converge to a solution for the specified model. While convergence cannot be guaranteed, you might want to try altering the default optimization options available in the NLOPTIONS statement. See the NLOPTIONS statement description in the Syntax section of the QLIM documentation. For instance, changing the optimization technique (NLOPTIONS TECH= option) or increasing the maximum number of iterations (NLOPTIONS MAXITER= option) might be helpful. Options for alternative stopping criteria are also available. The options for displaying the optimization history may provide useful information. See the Details of Optimization Algorithms section for information about the optimization algorithms and suggestions. If you are unable to obtain proper convergence for the specified model, you may need to consider fitting a simpler model, that is, a model that has fewer parameters.