Excel could not be started - SAP Best practices

Hi Gurus,

I am started to do sap best practices for PP , In KEPM --> Operating concern (US_20 - Best practices). When i double click the Planning method, It shows like Excel could be started. As i searched SCN - no relevant Tcodes are mentioned for this case because this thing  is happened only for this operating concern. Well other operating concern are working well..

Regards,

Dinesh.