"This server has mods that require FML/Forge to be installed on the client."

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    i used a curse forge modpack (the pixelmon mod) both on my server and client but "This server has mods that require FML/Forge to be installed on the client. Contact your server admin for more details." always shows up when i try joining

    Quote from Aimshia

    i used a curse forge modpack (the pixelmon mod) both on my server and client but "This server has mods that require FML/Forge to be installed on the client. Contact your server admin for more details." always shows up when i try joining

    You also need to install the modpack on your PC using the CurseForge app or a different launcher like Prism Launcher or ATLauncher.