Do not waste time on random tweaks. Follow this structured, best-practice workflow:
Situation: 3D fill simulation fails with error 99998 shortly after start. Action taken: autodesk moldflow error 99998 best
Result: Error resolved; overall simulation time reduced by improved mesh. Do not waste time on random tweaks
Run Mesh > Mesh Tools > Connectivity Assistant. Result: Error resolved; overall simulation time reduced by
Error 99998 is a generic numerical failure code. Unlike Error 1005 (mesh issues) or Error 3001 (material data), Error 99998 indicates that the solver encountered a mathematical operation it could not complete—typically during the filling, packing, or warpage stages.
Common error text variations:
The keyword here is best – meaning the most effective, proven solutions.