I've searched through the forums and haven't seen this mentioned yet.
I have made 2 sites using silverstripe and both have the excellent eCommerce module. One website works perfectly - meaning I can access the reports, then I get an error on the next website when I access the reports tab and all I get is a small red error at the bottom of the window saying 'Error loading page'. Thats the only issue I get.
I'm not sure where to begin to figure out how to solve this. Anyone else had this issue?