This message appears when (i) the Solver has completed the maximum number of iterations, or trial solutions, allowed for the Iterations option in the Task Pane Engine tab and (ii) you clicked on the Stop button when the Solver displayed the Show Trial Solution dialog.  You may increase the value in the Iterations box, or click on the Continue button instead of the Stop button in the Show Trial Solution dialog. But you should also consider whether re-scaling your model or adding constraints might reduce the total number of iterations required.

If you are solving a mixed-integer programming problem (any problem with integer constraints), this message is relatively unlikely to appear.  The Evolutionary Solver uses the Max Subproblems and Max Feasible Solutions options on the Limit Options dialog tab, and the Branch & Bound method (employed by the other Solver engines on problems with integer constraints) uses the Max Subproblems and Max Integer Solutions options on the Integer Options dialog tab, to control the overall solution process.   The count of iterations against which the Iteration limit is compared is reset on each new subproblem, so this limit usually is not reached.

If you are using Stochastic Decomposition to solve for a stochastic linear model in Analytic Solver Desktop, this status will be returned if the algorithm performs over 5,000 iterations.