Why does an Excel 2007 file lose its format when reopened?
 

An Excel 2007 file (e.g. File.xlsx) loses its formatting when it is reopened.

Why does an Excel 2007 file lose its format when reopened?
 

You may have too many cell formats/styles. To see if that's possibly true,
click on the Cell Styles "More" arrow and see if you have a gazillion styles
showing. If that's true, you can remove unused styles by saving the workbook
as a web page, closing, reopening, save as a normal workbook.

"Chrystopher" wrote:

An Excel 2007 file (e.g. File.xlsx) loses its formatting when it is reopened.