We've found that creating schedules with instance names longer than 70 characters are causing the schedules to fail with the following error message:
Could not open the file C:\Program Files (x86)\SAP BusinessObjects\SAP BusinessObjects Enterprise XI 4.0\FileStore\Output\a_021\026\000\6677\012345678901234567890123456789012345678901234567890123456789012345678901_30_9126521297334807839-guid[afd91171-3616-4e8e-a942-f51e55b107fb1].xlsx.
When we shorten the instance names to less than 70 characters the schedules process successfully. Schedule instance names over 70 characters are currently processing successfully in 3.1 SP7.