3Ds Max file contains viruses
Viruses in 3Ds Max scenes are a common problem that Autodesk struggles with.
In case when opening a file, 3Ds Max informs you that a virus has been found in this file, you need to use special plug-ins to eliminate these viruses.
There is official and unofficial software. The best options are:
3Ds Max Scene Security Tools
3ds Max Scene Security Tools is Autodesk's recommended option to detect and remove third-party malicious scripts. Malicious scripts can damage the 3ds Max environment, cause data loss and instability, and spread to other systems by sharing 3ds Max scene files.
Prune Scene
The second option is Prune Scene with more advanced functionality.
With Prune Scene, you can clean your 3Ds Max scene from script viruses and accumulated debris.
This allows, in some cases, to significantly reduce the size and speed up saving the scene.