Changes Dates Automatically P6

Hello everybody,

In Microsoft Project when i change the date of one activity the others activities change the start date automatically, but in P6 i can´t.

I go to Edit/User preferences and click Reorganize automatically, then press F5 and the activities don’t change.

So i choose the chart view, select all activities, right click/ reorganize all and the activities don’t change.

Tools/Reorganize now and nothing.

Any can hepl me please?

Regards,

Felipe