I'm having trouble with data PowerPivot data refresh...
I have made 2 workbooks:
1 - Put some random data, to use this workbook as a data source. I put it on SharePoint server PowerPivot gallery...
2 - I made another workbook, select data source
put some dynamic table... and work with data.
When the second workbook is on my desktop... I can work with it without a problem.
But, when I put the workbook on SharePoint
(http://spserver/reports/report01.xls) and access this via Excel Web App... I can't filter data, can't update anything... so... not working.
Access was denied by the external data source. The following connections failed to refresh: mycustom datasource
Where can I found error log? Windows Log Event ?! How can I troubleshoot this type of error?