I am working on an Underground GRE system (@1150 Nodes). Surge load spectra is applied for Dynamic Time-History Analysis at 80 locations.
(I should apply at 125 locations but 80 is limit for CII)

After completing all required Dynamic input, error checker shows no error. While running the analysis I get Fatal error #721

- If there is any error in Input, why it is not visible during error check.
- How to correct the model for Error #721?

(relevant files are also forwarded to support "ppmcrm@intergraph.com")

Regards,
Dnyanesh