JavaCard OS

I want to do pre-personalization on a J2A040 card. And I know pre-personalization procedure.
But when I send the SELECT command to select the ROOT applet, the card returns ERROR status word 0x6A81, has anyone encountered this problem when doing pre-personalization on JCOP card? Please guide how to resolve this problem. Thanks in advance.

6A 81: Function not supported

Do you know the card transport key? Just use this key as the AID in the SELECT command.

Wow, I used transport key as the AID in the SELECT command. it works. Many thanks for your help.

You mean that just by initializing the card with the 00A4040010 TK KEY command, in my case is a J2A040,

we can download applets and use it to develop with the default keys, so there is no need for the pre-personalized the card,

to learn javacard language at home we can develop a client who uses the card, the applet which is downloaded, is that right ?

In the case of a professional application it is necessary to pre-personalized it for change ATR and KEY and protect it and fuse.

This is what I’m trying to do but I’m super new to all this, does anyone have a step by step guide to pre personalize these cards?