Specifies the step increment for a progress bar. The step increment is the amount by which the progress bar increases its current position whenever it receives a PBM_STEPIT message. By default, the step increment is set to 10.
PBM_SETSTEP
wParam = (WPARAM) nStepInc;
lParam = 0;
Returns the previous step increment.
Version 4.00 and later of Comctl32.dll
Windows NT/2000: Requires Windows NT 4.0 or later