Client created a custom report with filters and tested it. Report run fine. When he scheduled the report to run and send to email, it never arrives.
The client named the report "Copy/Print/Disb Daily Report".
When the system tried to generate the report to the Temp folder, it interpreted the "/" characters in the report as sub folders under Temp.
Looking at the Event Viewer, the error message generated was: "Could not find a part of the path C:\Users\service account\AppData\Local\Temp\Copy\Print\Disb Daily Report.pdf"
Renaming the report (removing the slashes) to "Copy Print Disb Daily Report" resolved the problem.