This error occurs when the Report Viewer cannot pre-render the project drawings into its internal format. The root cause is almost always overly complex User Defined Product (UDP) symbols in the project.

The Report Viewer pre-renders every drawing in the project to SVG before generating any report — even for reports that do not display drawings, such as cable schedules. A project containing UDP symbols imported from DWG or similar sources can contain extremely complex geometry (polylines with tens of thousands of control points), which causes the pre-render to run out of memory or fail.

First check: look at the project file size. A simple project with a handful of drawings should be well under a megabyte. If your file is several megabytes or larger, a complex UDP symbol is the likely culprit.

Resolution: open the affected UDP in the Symbol Editor and check the Shape Count. If it runs to thousands, the imported geometry needs to be simplified — replace complex polylines with native Line and Arc objects. See also the Drawing & Editing FAQs for more on UDP performance.

Interim workarounds while you simplify the symbols: reduce the number of drawings in the project, or turn off all layers except Front High Detail and Parts before generating the report.