If you have files in the following folder $PS_CFG_HOME/appserv/prcs/<dbname>/files with extension xls, cxv , pdf and you try to schedule a query using Schedule Query (PSQUERY), and select email option, you may get incorrect file emailed to you.
Workaround: Delete the files in $PS_CFG_HOME/appserv/prcs/<dbname>/files folder that has extension xls, csv or pdf.
This is a bug introduced in 8.50.08 and as of 8.50.12 not yet resolved.
See My Oracle Support resolution ID: 1186374.1
PS resolution says this happens when you have PS_FILEDIR is setup in the Process scheduler box, but this was not the case in our environment.