specify the language of the title or description that will be set
public static bool SetItemUpdateLanguage(UGCUpdateHandle_t handle, string pchLanguage) { InteropHelp.TestIfAvailableClient(); using (var pchLanguage2 = new InteropHelp.UTF8StringHandle(pchLanguage)) { return NativeMethods.ISteamUGC_SetItemUpdateLanguage(handle, pchLanguage2); } }