If your model includes beam elements (runners or cooling channels) connected to 3D Tetrahedral elements:

If you try to run an analysis that overwrites an existing .mfr result file that is either:

| Cause | Likelihood | Fix Priority | |--------|------------|----------------| | Temp drive full | High | 1 | | Too many output steps | High | 2 | | 32-bit solver mode | Medium | 3 | | Antivirus blocking | Medium | 4 | | Corrupt study | Low | 5 | | Path length limit | Low | 6 |

Real-time antivirus scanners (McAfee, Norton, Windows Defender) sometimes lock the .tmp files Moldflow creates in the %TEMP% folder. When the solver tries to write to a locked buffer, it sees it as “full” and throws error 99998.

If the simulation crashes within the first few seconds or iterations, the initial conditions are often to blame.

While obvious, start here. Moldflow analysis files (.mfr, .m3r, .ow3) can grow very large—sometimes 50–200 GB for complex 3D warp analyses.

What to do:

Important: Moldflow creates multiple temporary files during solving. Even if your project drive has space, the system temp drive might be full.

The most common fix. Moldflow creates thousands of small files during solving; a cluttered temp folder causes crashes.