Signs executable files intended to be run on jailbroken Windows RT 8.1 Devices
Even when using the Golden Keys / Longhorn or Yahallo jailbreaks and with Test Mode enabled, third party applications under Windows RT 8.1 are still required to be test signed. For any application not distributed in an already signed state, SignTool will sign individual files or the executable content of entire folders with minimal user interaction.
Third party applications do not have to be test signed when running on Windows 10 Build 15035 or if being run under Windows RT 8.1 with UMCI Audit Mode enabled.


  • A Windows installation with the .NET Framework v4.0 or above (Any architecture).
  • If SignTool is being run on Windows RT 8.1 then the Golden Keys / Longhon or Yahallo jailbreak must already be installed and Test Mode must be enabled.


Download SignTool from the link below.


  1. 1.
    Right click on the downloaded file and select "Extract All..."
  2. 2.
    Select a destination for the extracted files.
  3. 3.
    Click "Extract".

Running SignTool

For executables that have dependencies such as DLL files it is easier to to use the "Sign folder" option instead of signing the all files individually.
  1. 1.
    Open SignTool.exe.
  2. 2.
    Click "Sign file" or "Sign folder".
  3. 3.
    Navigate to the file or folder to be signed and click "OK" or "Open".
  4. 4.
    Wait for operation to complete.
  5. 5.
    Close SignTool.


Application Doesn't Run

Unsigned Winfile.exe failing to run with Test Mode enabled.
If the above error is displayed when attempting to run an application on a jailbroken Windows RT 8.1 installation then attempt to resign the application and then verify the executable and any dependencies are signed correctly.

Verify Signing

  1. 1.
    Right click on a file that has been signed and select "Properties".
  2. 2.
    Click the "Digital Signatures" tab.
  3. 3.
    If "DesktopApp" is present in the "Signature list" then the file has been signed successfully.
Successfully signed Winfile.exe file properties

Version History

04/08/2022 - SignTool v1.1.1

  • Removed some duplicate code and did some minor refactoring.
  • Added .sys file support.
  • Removed annoying prompt after EVERY file.
  • Added proper copyright notice.
  • Renamed main class from Form1 to SignForm.
  • Now compiled with Visual Studio 2022.

15/10/2015 - SignTool v1.0.0

  • Automated signing of EXE or DLL files.


SignTool v1.0.0 - @eisbaer82 (XDA Developers Thread) SignTool v1.1.1 - @Starfrost