I've been working with expressing constraints using SolverAdd in VBA and have encountered the "missing constraints" bug as others.

It would perhaps be helpful to know: When the problem is encountered AND when the problem appears to be solved AND PERHAPS when Excel and a workbook is opened: What is the state of the constraints in the Solver Parameter dialog? i.e.Open Data, Solver to get the Solver Parameters dialog and examine the Constraints list there. This appears to be the only way to really compare results.