@Carl Love Ah, yes. Now it works, kind of..

I now get a value though, but no unit. I guess I have to setup my equilibrium equation and manually isolate O_L, before calculating a result.. Just thought it would be possible to solve it from the start without having to do a manual operation first...

@tomleslie 

@Carl Love

Ok, I uploaded my file for you guys to see, I now realize i should've just done that to begin with... And thanks for the responses so quickly! :)

Tom, I know you suggest no using the kN*m and kN/m, but the reason I need it is when i calculate torque and distributed load problems. 

Carl, if I replace O_L with O_L*kN, i get error message:

Warning, solving for expressions other than names or functions is not recommended.
 

But good info you guys, really helping me better understand how things work.