Assume that a PowerPivot workbook is located on a Microsoft SharePoint site that has Microsoft SQL Server PowerPivot for SharePoint configured. When you try to refresh the PowerPivot workbook, you may receive an error message that resembles the following:
File System Error: The following error occurred when reading from the file 'Compressed Stream'.
This issue occurs because the connection between SQL Server Analysis Services and Excel Calculation Services on the SharePoint site is dropped when the Internet Information Services (IIS) server that hosts the SharePoint site is being reset.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
To work around this issue, try to refresh the PowerPivot workbook again.