Missing multiple .dll files error when launching Fusion

Autodesk Support

Feb 28, 2025

Products and versions covered

Issue:

Users reported that when launching Fusion an error is shown that .dll files are missing. For example: acgx225.dll, qt5core_ad_5.dll, qt5gui_ad_5.dll, AclPCx64.dll, qt6gui.dill, qt6Widgets.dll, and Nsbase10.dll.

The example notification can be:

Fusion360.exe - system error

Code execution cannot continue because Qt5Core_Ad_5_12.dll was not found.

Solution:

To gain access to Fusion again, see the following:

Repair Fusion using the Service Utility. See Overview of Repair Fusion Command from Fusion Service Utility.
If the repair does not work, try uninstalling Fusion and reinstalling it using the latest installer from manage.autodesk.com
Configure antivirus software for Fusion as described here: Configuring anti-virus software for use with Fusion.
If the Service Utility fails to start, and it does not recover even after restarting the PC, try performing a manual clean uninstall of Fusion and then reinstalling the program. See How to do a manual uninstall of Autodesk Fusion.

Products:

Fusion;

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