: PeaZip is frequently recommended for these environments.

: Ensure you have downloaded all segments of the archive (e.g., Boing366K.part1.rar through to the final part) and placed them in the same directory.

The file is the second part of a multi-part split archive. To access the contents within this file, you cannot open it individually; you must have all related parts (e.g., part1.rar , part2.rar , etc.) in the same folder. How to Extract Multi-Part RAR Files

Do you have of the archive downloaded and saved in that same folder?