What (game, document, software) you expect it to be?
Ensure you have SDF part 1.rar , SDF part 2.rar , SDF part 3.rar , etc., in the same directory. SDF part 3.rar
Right-click only the first file ( SDF part 1.rar or SDF.part1.rar ) and choose "Extract Here." The software will automatically pull data from all parts to reconstruct the original file. If you can tell me: Where you found or downloaded this file? What (game, document, software) you expect it to be