First of all, which version of Max and do you in fact have V-Ray installed? Sometimes people don't have V-Ray and that's why the materials are missing.
If you do have V-Ray have you searched your entire hard drive for the names of the missing files? Maybe they are in a non-standard folder for some reason.
Did you build that material or did you get it from somewhere, like on a model or something? If you got it from somewhere, could there have been a separate folder with bitmaps in it that you overlooked and didn't download?
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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