from
http://www.yubico.com/vipDual identity option
The VIP enabled YubiKey comes with its configuration password set to ensure the VIP credential is not accidentally overwritten as it cannot be recovered. The second identity slot is open and can be configured for either a Yubico OTP using the AES Key Upload Service, or with a static password. If you really do want to overwrite the VIP credential, the password is the same as the serial number (8 digits laser etched onto the key). If you are unclear about this paragraph - please refer to the Yubico manual on the documentation page.
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