How to register the JAD file extension

In former releases of the Wireloess Toolkit (WTK), the installation process also registered the JAD file extension as needed to run a JAD/JAR locally in the emulator. Unfortunately this never worked on Windows Vista or when you use the WTK or the new J2ME Software Development Kit (SDK) distributed with the mobility pack of the NetBeans IDE.

The registration of the JAD extension needs to run emulator.exe found in the bin-directory of the WTK or J2ME SDK with the following parameters

<path to WTK- or SDK-bin>emulator.exe Xdescriptor:"%1"

You can try to register the JAD extension manually, but with Windows Vista you need to patch the registry to add the parameters.

A simple workaround is to register an "emulator launcher" go.exe that spawns emulator.exe with the correct parameters. go.exe must reside in the same directory than emulator.exe, which normally is the bin-directory of the WTK or J2ME SDK.

Proceed as follows:

  1. Download
  2. Unpack go.exe and copy it in the bin-directory of the WTK or J2ME SDK (where emulator.exe resides)
  3. When you try to run a JAD file by clicking the file icon in the Windows Explorer or selecting a browser link (example here), the system requests you which program to use. With the dialog options search and choose go.exe

We guarantee that go.exe only spawns emulator.exe and has no other action.

In any case, if you have a problem or merely a question, send an e-mail to

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