检查Windows更新是否正常，并下载并安装.NET Framework 4.6或更高版本。

示例代码：

//检查是否安装了.NET Framework 4.6或更高版本 bool IsDotNetInstalled() { try { var dotNet45 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full", "Release", null); if (dotNet45 != null && (int)dotNet45 >= 393295) return true;

    var dotNet46 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.6", "Release", null);
    if (dotNet46 != null && (int)dotNet46 >= 393295)
        return true;

    var dotNet461 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.6.1", "Release", null);
    if (dotNet461 != null && (int)dotNet461 >= 393295)
        return true;

    var dotNet462 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.6.2", "Release", null);
    if (dotNet462 != null && (int)dotNet462 >= 393295)
        return true;

    var dotNet47 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.7", "Release", null);
    if (dotNet47 != null && (int)dotNet47 >= 461308)
        return true;

    var dotNet471 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.7.1", "Release", null);
    if (dotNet471 != null && (int)dotNet471 >= 461308)
        return true;

    var dotNet472 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.7.2", "Release", null);
    if (dotNet472 != null && (int)dotNet472 >= 461308)
        return true;

    var dotNet48 = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4.8", "Release", null);
    if (dotNet48 != null && (int)dotNet48 >= 528040)
        return true;

    return false;
}
catch (Exception)
{
    return false;
}

}

//下载.NET Framework 4.6或更高版本 public static void DownloadDotNet() { string url = "http://download.microsoft.com/download/9/5/A/95A9616B-7A37-4AF6-BC36-D6EA96C8DAAE/NDP46-KB3045557-Web.exe";

WebClient wb = new WebClient();
wb.DownloadFile(url, "path_to_exe_file/NDP46-KB3045557-Web.exe");

//运行.NET Framework安装程序
Process.Start("path_to_exe_file/NDP46-KB3045557-Web.exe", "/passive /norestart");

}