Laserfiche only has built-in support for a page-by-page content comparison between MS Word documents. It doesn't work for Excel files. Excel 2013 in Office 2013 Professional Plus and later can compare workbooks, so if you have that, you can export both versions as local files from the Client to your workstation, then open one of the files in Excel and then choose the Compare Files command. More details are available at https://support.office.com/en-us/article/Compare-two-versions-of-a-workbook-by-using-Spreadsheet-Compare-0e1627fd-ce14-4c33-9ab1-8ea82c6a5a7e

We'll add built-in support for this to a future release of Laserfiche, provided you have a copy of Excel installed which supports this feature.