The file name you provided ( download-cod-united-offensive-apun-kagames-part2-rar ) indicates a split archive. Here is what you need to know for a successful installation:
This review covers , specifically evaluating its content, gameplay improvements over the base game, and technical aspects related to multi-part archive files like the one you mentioned. Game Overview download-cod-united-offensive-apun-kagames-part2-rar
The expansion introduced several mechanics that became staples in later military shooters: specifically evaluating its content