Your help will be highly appreciable for the below context.
While trying to open a report output, following error occurs and won't show the PDF format correctly.
"There was an error processing a page. There was a problem reading this document(135)".
Object Type : Reports 10g with graph
Conc Program Output Type : PDF
Note: Currently issue happening only in DEV instance not in UAT/Prod instance.
When you click View Output, press the Control key and see if you get an open/save dialog. If one is displayed, save the document and try opening it directly from the PDF reader.
If this does not resolve the issue, post a screenshot of the error.