Each time you load a project you are given the option of enabling or disabling the code within that project as a protection against viruses.
If you enable the code, viruses in the code can begin executing. If you disable the code, the project will still be loaded, but all code within that project is prevented from running. The virus alert is not displayed when you load a project by dragging a DVB file from Windows Explorer or File Explorer, and dropping it into an open drawing in the AutoCAD window.