One by One Step selection

Hi!

I’m really new here and still working on the first steps with BLENDER.

My PROBLEM is that whatever I try, it is not possible for me to select several vertices; edges; or faces using the “one by one Step selection” method.:no:

All the other shortcut keys and Selection types work fine, but though I am in the edit mode Blender just ignores SHIFT while I am trying to select several vertices by RMB.

Is there something else I have to have in mind???

Alright I fixed on my own! Another program used the same shortcut key combination at the same time and blocked it meanwhile in Blender!