I converted an Excel spreadsheet to the open source LibreOffice and Open Office. As a result, it changed many of the fill colors from clear/white to red. I did not want this to happen. Now I am back to using MS Excel 2013. How can I easily change the fill color red back to fill color white, without having to do it manually, for the thousands of cells that were changed to red? I am a beginning to intermediate skill level user of Excel.