Why my Visual Studio offline installer requares an internet while installing?

I followed the instructions i found on the internet about making an offline installer for Visual Studio 2017 and made an offline installer (about 31 GB) for VS 2017 but when i begin to install i found the installer downloading the files needed to install instead of using the downloaded files and when i prevent the installer from using the internet, it gives me an error and says that it cannot connect to the internet, What should i do to make it use the downloaded files

here is the image of the error : enter image description here

here is the image of the installer file : enter image description here

and here is the log i see when i click on "View log" :

The product failed to install the listed workloads and components due to one or more package failures.

Incomplete workloads
    Desktop development with C++ (Microsoft.VisualStudio.Workload.NativeDesktop,version=15.0.26403.0)
    Game development with Unity (Microsoft.VisualStudio.Workload.ManagedGame,version=15.0.26323.1)
    Linux development with C++ (Microsoft.VisualStudio.Workload.NativeCrossPlat,version=15.0.26323.1)
    Mobile development with .NET (Microsoft.VisualStudio.Workload.NetCrossPlat,version=15.0.26403.0)
    Universal Windows Platform development (Microsoft.VisualStudio.Workload.Universal,version=15.0.26403.0)

Incomplete components
    .NET Native (Microsoft.Component.NetFX.Native,version=15.0.26208.0)
    C++ profiling tools (Microsoft.VisualStudio.Component.VC.DiagnosticTools,version=15.0.26208.0)
    Graphics debugger and GPU profiler for DirectX (Microsoft.VisualStudio.Component.Graphics.Tools,version=15.0.26208.0)
    Universal Windows Platform tools (Microsoft.VisualStudio.Component.UWP.Support,version=15.0.26412.1)
    Universal Windows Platform tools for Cordova (Microsoft.VisualStudio.ComponentGroup.UWP.Cordova,version=15.0.26403.0)
    Universal Windows Platform tools for Xamarin (Microsoft.VisualStudio.ComponentGroup.UWP.Xamarin,version=15.0.26403.0)
    VC++ 2017 v141 toolset (x86,x64) (Microsoft.VisualStudio.Component.VC.Tools.x86.x64,version=15.0.26208.0)
    Visual C++ for Linux Development (Component.MDD.Linux,version=15.0.26208.0)
    Visual Studio Tools for Unity (Microsoft.VisualStudio.Component.Unity,version=15.0.26323.1)
    Windows 10 SDK (10.0.15063.0) for Desktop C++ x86 and x64 (Microsoft.VisualStudio.Component.Windows10SDK.15063.Desktop,version=15.0.26403.0)
    Xamarin (Component.Xamarin,version=15.0.26424.2)
    Xamarin Profiler (Component.Xamarin.Profiler,version=15.0.26228.0)
    Xamarin Remoted Simulator (Component.Xamarin.RemotedSimulator,version=15.0.26228.0)
    Xamarin Workbooks (Component.Xamarin.Inspector,version=15.0.26228.0)

You can search for solutions using the information below, modify your selections for the above workloads and components and retry the installation, or remove the product from your machine.

Following is a collection of individual package failures that led to the incomplete workloads and components above. To search for existing reports of these specific problems, please copy and paste the URL from each package failure into a web browser. If the issue has already been reported, you can find solutions or workarounds there. If the issue has not been reported, you can create a new issue where other people will be able to find solutions or workarounds.

Package 'Microsoft.SmartDevice.Connectivity.CoreRuntime,version=15.0.26208.0' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10675398/acc6dbec6a2779df88bf4f51a167165e/netfx_CoreRuntimeForCoreCon.msi'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Microsoft.SmartDevice.Connectivity.CoreRuntime;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Mobile development with .NET (Microsoft.VisualStudio.Workload.NetCrossPlat,version=15.0.26403.0)
        Universal Windows Platform development (Microsoft.VisualStudio.Workload.Universal,version=15.0.26403.0)
    Impacted components
        .NET Native (Microsoft.Component.NetFX.Native,version=15.0.26208.0)
        Universal Windows Platform tools (Microsoft.VisualStudio.Component.UWP.Support,version=15.0.26412.1)
        Universal Windows Platform tools for Cordova (Microsoft.VisualStudio.ComponentGroup.UWP.Cordova,version=15.0.26403.0)
        Universal Windows Platform tools for Xamarin (Microsoft.VisualStudio.ComponentGroup.UWP.Xamarin,version=15.0.26403.0)
    Details
        WebClient download failed: Unable to connect to the remote server
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'Microsoft.VisualStudio.DotNetNative.ILC,version=15.0.26228.0' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10676414/47fc915fac7508ebee91f0495338c675/netfx_NativeCompilationBuild.15.0.msi'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Microsoft.VisualStudio.DotNetNative.ILC;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Mobile development with .NET (Microsoft.VisualStudio.Workload.NetCrossPlat,version=15.0.26403.0)
        Universal Windows Platform development (Microsoft.VisualStudio.Workload.Universal,version=15.0.26403.0)
    Impacted components
        .NET Native (Microsoft.Component.NetFX.Native,version=15.0.26208.0)
        Universal Windows Platform tools (Microsoft.VisualStudio.Component.UWP.Support,version=15.0.26412.1)
        Universal Windows Platform tools for Cordova (Microsoft.VisualStudio.ComponentGroup.UWP.Cordova,version=15.0.26403.0)
        Universal Windows Platform tools for Xamarin (Microsoft.VisualStudio.ComponentGroup.UWP.Xamarin,version=15.0.26403.0)
    Details
        WebClient download failed: Unable to connect to the remote server
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'Microsoft.VisualCpp.CRT.x64.OneCore.Desktop,version=14.10.25017.0' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10677138/f3c8761386ddbbf09ce9fadf6bbe3e45/microsoft.visualcpp.crt.x64.onecore.desktop.vsix'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Microsoft.VisualCpp.CRT.x64.OneCore.Desktop;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Desktop development with C++ (Microsoft.VisualStudio.Workload.NativeDesktop,version=15.0.26403.0)
        Mobile development with .NET (Microsoft.VisualStudio.Workload.NetCrossPlat,version=15.0.26403.0)
        Universal Windows Platform development (Microsoft.VisualStudio.Workload.Universal,version=15.0.26403.0)
    Impacted components
        C++ profiling tools (Microsoft.VisualStudio.Component.VC.DiagnosticTools,version=15.0.26208.0)
        Graphics debugger and GPU profiler for DirectX (Microsoft.VisualStudio.Component.Graphics.Tools,version=15.0.26208.0)
        Universal Windows Platform tools (Microsoft.VisualStudio.Component.UWP.Support,version=15.0.26412.1)
        Universal Windows Platform tools for Cordova (Microsoft.VisualStudio.ComponentGroup.UWP.Cordova,version=15.0.26403.0)
        Universal Windows Platform tools for Xamarin (Microsoft.VisualStudio.ComponentGroup.UWP.Xamarin,version=15.0.26403.0)
        VC++ 2017 v141 toolset (x86,x64) (Microsoft.VisualStudio.Component.VC.Tools.x86.x64,version=15.0.26208.0)
    Details
        WebClient download failed: Unable to connect to the remote server
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'Microsoft.VisualCpp.PGO.Headers,version=14.10.25017.0' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10676565/40df9b1c8c5b3ac3eaba2181cec89a49/microsoft.visualcpp.pgo.headers.vsix'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Microsoft.VisualCpp.PGO.Headers;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Desktop development with C++ (Microsoft.VisualStudio.Workload.NativeDesktop,version=15.0.26403.0)
        Universal Windows Platform development (Microsoft.VisualStudio.Workload.Universal,version=15.0.26403.0)
    Impacted components
        C++ profiling tools (Microsoft.VisualStudio.Component.VC.DiagnosticTools,version=15.0.26208.0)
        Graphics debugger and GPU profiler for DirectX (Microsoft.VisualStudio.Component.Graphics.Tools,version=15.0.26208.0)
        VC++ 2017 v141 toolset (x86,x64) (Microsoft.VisualStudio.Component.VC.Tools.x86.x64,version=15.0.26208.0)
    Details
        WebClient download failed: Unable to connect to the remote server
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'Win10SDK_10.0.15063.Desktop,version=10.0.15063.12' failed to install.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Win10SDK_10.0.15063.Desktop;PackageAction=Install;ReturnCode=15605
    Impacted workloads
        Desktop development with C++ (Microsoft.VisualStudio.Workload.NativeDesktop,version=15.0.26403.0)
    Impacted components
        Windows 10 SDK (10.0.15063.0) for Desktop C++ x86 and x64 (Microsoft.VisualStudio.Component.Windows10SDK.15063.Desktop,version=15.0.26403.0)
    Log
        C:\Users\Ahmad Galal\AppData\Local\Temp\dd_setup_20170824011716_001_Win10SDK_10.0.15063.Desktop.log
    Details
        Command executed: "c:\windows\syswow64\\windowspowershell\v1.0\powershell.exe" -NonInteractive -NoLogo -NoProfile -ExecutionPolicy Bypass -InputFormat None "$ErrorActionPreference="""Stop"""; $VerbosePreference="""Continue"""; $ScriptPath="""C:\ProgramData\Microsoft\VisualStudio\Packages\Win10SDK_10.0.15063.Desktop,version=10.0.15063.12\WinSdkInstall.ps1"""; $SetupExe="""winsdksetup.exe"""; $SetupLogFolder="""windowssdk"""; $PackageId="""Win10SDK_10.0.15063.Desktop"""; $LogFile="""C:\Users\Ahmad Galal\AppData\Local\Temp\dd_setup_20170824011716_001_Win10SDK_10.0.15063.Desktop.log"""; $SetupParameters="""/features OptionId.DesktopCPPx64 OptionId.DesktopCPPx86 OptionId.SigningTools OptionId.MSIInstallTools OptionId.UWPManaged OptionId.UWPCPP /quiet /norestart"""; (gc $ScriptPath | out-string) | Invoke-Expression; if (!$?) { exit 1603 } elseif ($LastExitCode) { exit $LastExitCode }"
        Return code: 15605
        Return code details: There was a problem downloading your product.

Package 'Xamarin.Android.Sdk,version=7.3.1.2' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10677013/d68d54e233c956ff79799fdf63753c54/Xamarin.Android.Sdk.vsix'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Xamarin.Android.Sdk;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Mobile development with .NET (Microsoft.VisualStudio.Workload.NetCrossPlat,version=15.0.26403.0)
    Impacted components
        Xamarin (Component.Xamarin,version=15.0.26424.2)
        Xamarin Profiler (Component.Xamarin.Profiler,version=15.0.26228.0)
        Xamarin Remoted Simulator (Component.Xamarin.RemotedSimulator,version=15.0.26228.0)
        Xamarin Workbooks (Component.Xamarin.Inspector,version=15.0.26228.0)
    Details
        WebClient download failed: Unable to connect to the remote server
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'Xamarin.VisualStudio,version=4.5.0.486' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10676874/d68d54e233c956ff79799fdf63753c54/Xamarin.VisualStudio.vsix'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Xamarin.VisualStudio;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Mobile development with .NET (Microsoft.VisualStudio.Workload.NetCrossPlat,version=15.0.26403.0)
    Impacted components
        Xamarin (Component.Xamarin,version=15.0.26424.2)
        Xamarin Profiler (Component.Xamarin.Profiler,version=15.0.26228.0)
        Xamarin Remoted Simulator (Component.Xamarin.RemotedSimulator,version=15.0.26228.0)
        Xamarin Workbooks (Component.Xamarin.Inspector,version=15.0.26228.0)
    Details
        WebClient download failed: Unable to connect to the remote server
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'SyntaxTree.VisualStudio.Unity.Vsix,version=3.1.0.0' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10678396/d68d54e233c956ff79799fdf63753c54/SyntaxTree.VisualStudio.Unity.ENU.vsix'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=SyntaxTree.VisualStudio.Unity.Vsix;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Game development with Unity (Microsoft.VisualStudio.Workload.ManagedGame,version=15.0.26323.1)
    Impacted components
        Visual Studio Tools for Unity (Microsoft.VisualStudio.Component.Unity,version=15.0.26323.1)
    Details
        WebClient download failed: The remote name could not be resolved: 'download.visualstudio.microsoft.com'
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'SyntaxTree.VisualStudio.Unity.Msi,version=3.1.0.0' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10675229/d68d54e233c956ff79799fdf63753c54/vstu2017.msi'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=SyntaxTree.VisualStudio.Unity.Msi;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Game development with Unity (Microsoft.VisualStudio.Workload.ManagedGame,version=15.0.26323.1)
    Impacted components
        Visual Studio Tools for Unity (Microsoft.VisualStudio.Component.Unity,version=15.0.26323.1)
    Details
        WebClient download failed: The remote name could not be resolved: 'download.visualstudio.microsoft.com'
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'Microsoft.VisualStudio.VC.Ide.Linux,version=15.0.26412.1' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10678276/d1c2eef83e3d5c424c1289d9438ad112/microsoft.visualstudio.vc.ide.linux.vsix'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Microsoft.VisualStudio.VC.Ide.Linux;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Linux development with C++ (Microsoft.VisualStudio.Workload.NativeCrossPlat,version=15.0.26323.1)
    Impacted components
        Visual C++ for Linux Development (Component.MDD.Linux,version=15.0.26208.0)
    Details
        WebClient download failed: The remote name could not be resolved: 'download.visualstudio.microsoft.com'
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029

Package 'Microsoft.VisualStudio.VC.Ide.Linux.Resources,version=15.0.26419.1,language=en-US' failed to download from 'https://download.visualstudio.microsoft.com/download/pr/10675292/dbd9a23497bf8f7e1e3a3599311ca6ca/microsoft.visualstudio.vc.ide.linux.resources.vsix'.
    Search URL: https://aka.ms/VSSetupErrorReports?q=PackageId=Microsoft.VisualStudio.VC.Ide.Linux.Resources;PackageAction=DownloadPackage;ReturnCode=0x80072efd
    Impacted workloads
        Linux development with C++ (Microsoft.VisualStudio.Workload.NativeCrossPlat,version=15.0.26323.1)
    Impacted components
        Visual C++ for Linux Development (Component.MDD.Linux,version=15.0.26208.0)
    Details
        WebClient download failed: The remote name could not be resolved: 'download.visualstudio.microsoft.com'
        Bits download failed: File not found.
        WinInet download failed: Function: InternetOpenUrl, HR: -2147012867, Message: Unknown error 12029