you no longer see the selected area

[Giovannino60]

with autocad 2010 you can no longer see the selection area, i.e. when with the mouse from the bottom I climb up you no longer see the selection area, but the rows are selected, i.e. you see dotted. . I attach an image of another computer to better understand the question. . .
Thank you.

 

[Cristallo]

check the pick car variable (from keyboard type pick car) must be at 1, if it is at 0 type 1.
or in tools/options/selection click on implicit window