Defender
When you run kJams for the first time, Windows Defender may complain, and then kJams crashes (exits unexpectedly).
- Here is the complaint you'll see:

- Click the banner to get details, you'll see this:
________________________________________________
________________________________________________ - This is known to be a "false positive". See the word "Severe" there on the right? See the little downward pointing chevron under it? Click that.
- "User account control" may (or may not) now show a dialog that asks "Do you want to allow this app to make changes to your device", specifying that the app is "Windows Security". If you see this dialog, click "Yes".
- Now you should see this:

- Now click on the "Actions" button and pick "Allow", like this:

- Now run kJams again, and you'll have no problems.