Make sure you have part1.rar , part2.rar , etc., in one folder. Use a modern extractor: Use 7-Zip or WinRAR.
All parts (except the last one) should generally be the exact same size. If they aren't, one might be corrupted or fake. 🛠️ How to open it WULNOT-MW.part3.rar
Use a tool like VirusTotal to scan the file before extracting it. Make sure you have part1