topic Re: NTAG424 ChangeKey not working in TagXplorer in NFC

NTAG424 ChangeKey not working in TagXplorer

GlennN — Mon, 30 Oct 2023 12:50:04 GMT

Hi, I am trying to use TagXplorer to change the access keys on NTAG424 tags, I have an application which uses the Proprietary file to store application data amd I want to use Key 2 for read access and Key 3 for read/write. Setting of the access conditions works fine but up until now we have been using the default keys of 0000000..........

I now want to change to 'real' values for these keys. I have been using TagXplorer to authenticate with key 0 and then using the 'Change Key' tab to try and set a new key:

When I click on 'Change Key' button nothing happens, I get no success or error messages and the log shows only the original authentication:

I am using a HID 5022CL reader if that makes any difference

If I got an error or something then I could deal with that but no response at all is hard to debug!!

Any help gratefully received

Re: NTAG424 ChangeKey not working in TagXplorer

Julián_AragónM — Tue, 31 Oct 2023 18:22:27 GMT

Hi @GlennN,

As TagXplorer is no longer updated, RFIDDiscover is recommended instead. Please try to change the keys from the RFIDDiscover software instead.

Also, AN12196 has useful information for changing the keys, please help me taking a look.

Best regards,
Julián.

Re: NTAG424 ChangeKey not working in TagXplorer

GlennN — Wed, 01 Nov 2023 09:27:54 GMT

@ Julián_AragónM I did also try to use RFIDDiscover but I do not have any compatible hardware. I have also looked at AN12196 which has useful information but it certainly doesn't tell you why TagXploer might throw an exception.

I am currently exploring some 3rd party hardware and software

Re: NTAG424 ChangeKey not working in TagXplorer

Julián_AragónM — Fri, 03 Nov 2023 16:55:33 GMT

Hi @GlennN,

Could you please help me following the steps mentioned in this post to change keys?

Change Keys and "lock" NTAG DNA 424 - NXP Community

Best regards,
Julián

Re: NTAG424 ChangeKey not working in TagXplorer

GlennN — Thu, 02 Nov 2023 08:13:32 GMT

@Julián_AragónM

I am confused why you need help?

However, The steps shown in

https://community.nxp.com/t5/NFC/Change-Keys-and-quot-lock-quot-NTAG-DNA-424/m-p/1058604

are the steps I have been following, I can follow this procedure completely and everything is fine until I click the 'Change Key' button, when I do click it I get no response at all, no success or error message. And when I look in the command window I see that an exception was thrown by the Java virtual machine.

The only thing I can think of is that the authentication is somehow in the wrong mode? I am not sure if it is mandatory to do authentication in LRP mode or whether either AES or LRP mode is OK?

If the authentication mode is wrong then I would expect an appropriate error message not an unhandled exception!!

Re: NTAG424 ChangeKey not working in TagXplorer

Julián_AragónM — Fri, 03 Nov 2023 16:54:55 GMT

Hi @GlennN,

Could you please add an image about the Java exception that pops up? Also, please check if you have the latest version of Java.

Have you been trying these steps on a clean NTAG? If not, please reproduce the steps for changing the keys from the community on a clean tag.

Best regards,
Julián