How to: Delete custom number formats.
Solution:
Select 'Cells...' from the 'Format' menu and click the 'Number' tab. Select 'Custom' from the 'Category' list box, then, select and delete the specific format.
1) Select the 'Format' menu and select 'Cells...'. (The Format Cells dialog box appears.)
2) Click the 'Number' tab.
3) Select 'Custom' from the 'Category' list box.
4) Select the custom format to delete from the 'Type' list box.
Selecting the format to delete
NOTE: Custom formats are added to the bottom of the list.
5) Click 'Delete'.
6) Click 'OK' to save the change and close the 'Format Cells' dialog box.
