1. Go to Reports > Management Report > Utilities > Multi Editing > Item Master Multi Editing.

2. An Item Master Multi Editing window will appear. In 'Stock Status' set "Whole". Click on Accept.

3. A Closing Stock as on window will appear. Press enter on the selected item.

4. A Multi Editing window will appear. Click on All Items.

5. An Item Master Multi Editing window will appear. In 'Incl/excl .tax (for tax=0.00 0-ALL) ' set "All".Press enter. 

6. The cursor will wait in "For Tax" set "0".Press enter.

7. Then select "Excl." by pressing spacebar key.

8. The user will Type 'SURE'.

After following the above steps inclusive tax get changed into exclusive in all item.