Yubico Forum

I'm trying to set up a new YubiKey 4 following the instructions found here - https://developers.yubico.com/yubico-piv-tool/YubiKey_PIV_introduction.html

but the default PIN keeps failing on my Mac (running El Capitan 10.11.2).

>yubico-piv-tool -a change-pin -P 123456 -N 12345678
Failed verifying pin code, now 1 tries left before blocked.

Once it's blocked, the unblocking feature using the PUK works though, so I know the default PUK PIN is working.

>yubico-piv-tool -a "unblock-pin" 1
Enter puk:
Enter new pin:
Verifying - Enter new pin:
Successfully unblocked the pin code.

Anyone else encounter this issue?

I am using El Capitan as well and I haven't seen this issue. I just went through and ran some commands:

yubicos-MacBook-Air:bin yubico$ ./yubico-piv-tool -a change-pin -P 123456 -N 12345678
Successfully changed the pin code.
yubicos-MacBook-Air:bin yubico$ ./yubico-piv-tool -a verify-pin -P 12345678
Successfully verified PIN.
yubicos-MacBook-Air:bin yubico$ ./yubico-piv-tool -a "unblock-pin" 1
Enter puk:
Enter new pin:
Verifying - Enter new pin:
Successfully unblocked the pin code.
yubicos-MacBook-Air:bin yubico$ ./yubico-piv-tool -a verify-pin -P 1111
Successfully verified PIN.

I also locked out the PIN and was able to unblock the PIN, change it, and verify afterwards. Have you tried resetting the applet and trying again?