When you send a report to Excel, and you wish to save the report, you must select Save As, rather than Save.

On some computers if you select Save, you will change the template AccountEdge uses to send the report to Excel, thus corrupting the template.

If your Excel templates are already corrupted, you can resolve the problem by reinstalling AccountEdge, selecting a custom installation and installing just the spreadsheet templates.

You may also want to use the reports found under the Export Data tab in the Index to Reports.  These reports are formatted for exporting and use in PowerBI and are ‘flattened’ (headers are removed) and can be used in Excel too.