E5058

E5058 FATAL ERROR: E5058 NON-ZERO GLOBAL MASS MATRIX REQUIRED FOR ANALYSIS
Cause: In MODAL solutions, a non-zero global mass matrix is required to extract eigenvalues (natural frequencies) and eigenvectors (mode shapes). This is usually the result of not specifying material density.
Action: Correct the applicable material Bulk Data entry (MAT1, MAT2, MAT8, or MAT9) by specifying material density in consistent units.
Remarks: See Autodesk Nastran Reference Guide, Section 4, Bulk Data, for entry format.