ILP: integer linear problem

hi, i have code an ILP . some times he give me a feasible sollution and some times no. i want to store those N feasible solutions in a matrix ( i have done a loop on the ILP ). But it stopped and exit the implementation when he find a non feasible solution, and consequently the matrix will not containt the N solutions!! So how can i iliminate those non f.sol so that the loop continue the implementation and i can store all the N feasible sol? thanks