How can I remove a cell pattern without affecting the cell color or gridlines?

Here is what happened. I have a spreadsheet that is 100x100 cells. The
cells had various colors applied using the Format Cells/Patterns/Cell Shading
dialog. I temporarily wanted to flag these cells as DO NOT EDIT by adding a
pattern (light dots) using the Format Cells/Patterns/Pattern dialog. I went
back to remove the pattern using the same dialog, but the gridlines are no
longer visible. I looked in MS Help - they suggest clicking on the Fill tool
and selecting NO FILL. When I do this, the gridlines come back, but the cell
coloring is now gone. Is there a way to remove the pattern while preserving
the grid and original cell coloring? Thanks so much.