If you accidentally enter your pin code incorrectly 3 times, your YubiKey will become locked and need the pin code reset with the PUK. The PUK was setup during the Yubikey setup process and will needed to change/unlock/unblock your YubikeyYubiKey PIN. In the event this information is lost, the Yubikey YubiKey must be reset removing all certificates & stored logins.
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