How do I reset all filters in Extjs Grids?

Try this code:

grid.filters.clearFilters();

This should take care of both the grid and its underlying store.

When you do

 grid.store.clearFilter();

it can only clear the filters on the store but the grid's view doesn't get updated with that call. Hence to handle it automatically for both the grid's view as well as the grid's store, just use

grid.filters.clearFilters();

Hope it helps!

Cheers!