The files required to move a project from Delphi or Delphi 2 to Delphi 3 are just the DFM, PAS, and DPR. It is also important to move any resource files (.res), that have custom resources like cursors, icons, strings, etc. All the other files are going to be recreated by the compiler when a build all is done inside of Delphi 3. It is especially important not to bring over the DCU files as the format changes from version to version. You may get unknown identifier errors or other strange behaviors if you try to bring over DCU files.