1.While running such report export transactions make sure that you have only one active instance of Process Runner.
2.User should have proper authorization to download reports.
3.This feature is tested on SAP Version 710. Patch level should be installed.
4.Office Integration settings required before exporting report through Process Runner.
a.Launch SAP and type S_ALR_87013611
b. Navigate to Environment-> Options.
c. In Office Integration, select Microsoft Excel and click ok.
d. SAP will give a warning about the document containing Macros. Select “Always trust macros from this publisher” and click on “Enable Macros”.
e. Exit SAP.
f. You might have to check your macro settings in Microsoft Excel also.
For more information on how to do it refer Excel Macro Settings.