WinRAR/7-Zip will automatically detect .part2 and .part3 and assemble the full file.
To help you further, are you getting a specific (e.g., "CRC error," "Unexpected end of archive") when extracting? tramsim_vienna.part3.rar
To properly handle a multi-part RAR ( .part1.rar , .part2.rar , tramsim_vienna.part3.rar ), you must have: in the same folder. An extraction tool such as WinRAR or 7-Zip . 2. Steps to Assemble the Data WinRAR/7-Zip will automatically detect