How to clear formatting in all un-used cells in Excel

[spauwer]

Example:  Someone highlighted the row, added formatting, now rows K - end of time have lines in them.  Same for columns.  When I find the end of the 

[#2]

@spauwer 

Select all unused rows, then right-click in the selection and select Delete from the context menu.

Do the same for all unused columns.

[#3]

@Hans Vogelaar 

Thank you.  How do you select all unused rows?  When I select the end of the document (CTRL-End), it takes me to the last row of my used cells.

[#4]

@spauwer 

Select the first unused row.

Then press Ctrl+Shift+Down Arrow.

Delete the selected rows.

Select the first unused column.

Then press Ctrl+Shift+Right Arrow.

Delete the selected columns.

[#5]

Perfect. Thank you.
I was not doing this from the first unused place.