The ns_install_v3_b5.exe file you have requested: Mods / Multiplayer / Natural Selection / Releases / v3.0 / Natural Selection v3.0 Beta 5 - 152.12mb is not available. Perhaps try browsing all files for the game Half-Life and upload any files you want to share or are missing. This is the only information we could locate:
The fifth beta client release of the action-strategy mod Natural Selection (version 3.0). This installer will update any prior beta (1-4a) version of 3.0 to Beta 5 or installs a clean version. No previous version(s) are required. The full changelog has been stated in the Readme area.