some files. What should I do? Firstly, check that your DVD drive is functioning properly. Try to copy the files using another DVD drive, on a different computer if necessary. If you have verified that the files cannot be copied, please contact our support channels for further advice. In the meantime, you can begin to work with BFD (it will skip missing files meaning one less velocity layer for that Kit-Piece) by doing the following. When the error message appears, note down the filename and the folder where it resides, so you can go to that folder and copy across the remaining files in that folder. Continue copying the rest of the folders, and repeat these steps if it happens again.