Are you running the study from a network drive (Z: or Y:)? Moldflow struggles with high-latency connections. When the solver asks for exclusive write access over a slow VPN or WiFi, the handshake times out and throws Error 99998.
The Fix:
If you’ve completed all steps above and still see Error 99998 exclusive, gather the following for Autodesk Technical Support: autodesk moldflow error 99998 exclusive
Open a support case via Autodesk Account → Support → Cases, and attach these files. Mention "Error 99998 exclusive – troubleshooting steps 1-7 complete" to fast-track the conversation.
Real-time file scanning by tools like McAfee, Symantec, or Windows Defender can temporarily lock a .mfp or .sdy file for inspection. Moldflow sees this as an exclusive lock held by another process (the antivirus), and Error 99998 appears. Are you running the study from a network drive (Z: or Y:)
This is a sneaky one. If you have Windows File Explorer open and you have clicked on a .sdy or .mfr file, Windows locks that file to generate a thumbnail preview. Moldflow cannot get "exclusive" access because Windows is reading the header.
The Fix:
Autodesk regularly patches license management issues. For example, Moldflow 2023.2 specifically addressed a "99998 exclusive during 3D mesh" bug. Always apply the latest Updates (not just new versions) via Autodesk Desktop App.