There is two ways to do most things in BUZ and De-activating and Re-activating price grids is no different.
Single Grid
De-activate a grid
This is the simple way to de-active a grid, although if you want to do multiple grids it might be quicker to use the Import/export function
Select the grid
Press the de-activate button
Re-activate a Grid
Select
the “Include Deactivated” tick box
the grid you wish to re-activate
Activate