bar simulation

i have a bar that is applied a force from both side. bar has a hole in the middle of of it and at a certain point bar is fillet to a smaller area. i draft the solid model with solid works and saved it as sldt file and import it to the comsol. but when i try to simulate for stress analysis for fillet and hole...
a. bar gets deformation in the direction of where there is no external forces
b. comsol simulation gives 20% error compare to hand calculation from hibbeler mechanic of materials.
any idea what i am doing wrong, or is there any similar simulation i can compare mine . thank you .