This message appears when you click Solve if you’ve used the Solver Parameters dialog to define a chance constraint or an expected value or risk measure objective, but you’ve selected the Excel Interpreter on the Options tab of the Solver Model dialog.  The PSI Interpreter can handle these types of constraints or objectives, without using PSI Statistics functions on the worksheet.  But the Excel Interpreter cannot do this; you must use PSI Statistics functions to summarize the array of sample values represented by the objective and each constraint that depends on uncertainty.  For example, you can compute a VaR-type chance constraint with a PsiPercentile() function.  If you are using Analytic Solver Upgrade, the Excel Interpreter is your only option, so you must use PSI Statistics functions on the worksheet.