Why are my borders or gridlines not showing up in my Excel sheet?

1. Check to make sure borders are enabled in the formatting settings of the cells.
2. Verify the page margins are correct by going to File>Page Setup in the menu bar.
3. Make sure that Page Breaks are not enabled in Page Setup.
4. Check to see if/ how many sheets have been frozen in the window.
5. Highlight the section and press CTRL+1 to format the cells; ensure that the ‘borders’ tab is selected.