Sometimes, no five-axis solution is possible. This occurs when the tool is so short, or perhaps the holder is so large that no matter what inclination angle is tried,

a collision will always result. Does the CAM system stop at this point, does it fail to produce a cutter path at all or does it inform you of the problem areas?
Naturally, forcing a lot of trial and error on the user, recalculating entire cutter paths is counterproductive. It is best if the problem areas are highlighted, with the possibility of using a longer tool, smaller toolholder or simply editing out those points.