Support reactions available in the Navigator - Results tab will activate the support reactions graphically due to the applied static loads. These are the equal and opposite forces at the supports to resist the applied loads. All magnitudes are positive with the arrow indicating the reaction direction.
However, in the table results Static Analysis - Results by Node - Support Forces tab, you'll notice that while the magnitudes are identical to the graphical display, the signage is opposite. This is due to the fact that the "forces" are given in this table directly vs. the "reactions" which are shown graphically as explained above.
Users have the ability to turn on the table signage graphically under the Navigator - Results tab - Support Reactions - With Sign.