Go to 'C:\Users\%Your User%\AppData\Local\Autodesk\3dsMax\2019 - 64bit\' and find the 'ENU' folder. Rename it so something like 'ENU_ORIGINAL'. Then restart Max. It will build a brand new one. See if the icon comes back. If so and you haven't done much customization of Max, you'll be good to go without too much effort.
If you have customized a lot, there are ways to protect and save a good bit of that configuration. You can search here and Google for info on that. It's out there. But the main thing is to get you going so you can finish your project.
By saving the original ENU above, you can always get back to that somewhat broked state if you need to. Just delete the new one you made, rename the original one back to just 'ENU' and restart Max.
Rob Holmes

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3ds Max (2023-2025), V-Ray 6.2, Ryzen 9 3950-X Processor, DDR 4 128MB, Gigabyte Aorus X570 Master motherboard, Sabrent Rocket NVMe 4.0 M.2 drives, NVidia RTX 4090, Space Pilot Pro, Windows 11 Pro x64, Tri-Monitor, Cintiq 13HD, Windows 11 x64
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