I am modeling a simply supported beam and the shear diagram created by simulation is showing shear values as negative when they should be positive.  A point load (downward on the beam) and a distributed load (downward) are supported by a pin on the left end and a roller on the right end of the beam.  When I recreated the model in a fresh file, same boundary conditions, same loadings, same material, answers turned out correctly. Any ideas as to why I am unable to edit the boundary conditions and loadings, re-mesh and run, and still not get correct answers in the original file?  Thanks for your help.