Root How to encrypt a rooted device?



I already discovered this Thread ->

but unfortunately, the solutions presented there did not solve the following issue:

I am trying to encrypt my rooted Samsung Galaxy S4 (or GT-I9505). I am using CF-Auto-Root. Originally i wanted to reset the KNOX-Counter to zero with Triangle Away. It did not work on Android 5.0.1, so i downgraded to Android 4.4.2 and then i could reset the counter.

I decided to stay on Android 4.4.2 and i wanted to encrypt the entire phone. After setting the password and starting the encryption the screen instantly goes black and does not show anything. After 10 or 15 minutes it suddenly restarts but without having applied the encryption. It has started without having asked the password before boot. I retried it several times but same result.

Then as mentioned in the thread above, i installed busybox and killed deamonsu over adb shell and started again the encryption. But even this time the screen went instantly black for a very long time (like two hours) and restarted again without having applied the encryption.

I am wondering now if its possible at all to fully encrypt a rooted phone?

Is there any chance to encrypt it?