Attempting to Upload the CSV YubiKey Seed File but Getting an Error Showing Duplicates or Invalid
Nov 25, 2025
Multi-Factor Authentication
Overview
When attempting to upload the CSV YubiKey Seed File, an error indicating duplicates or invalid data appears, even after reprogramming several keys with the correct YubiKey Configuration Slot.
No new YubiKey added to database.
Seeds are either duplicates or not applicable.
Applies To
- YubiKey
- Multi-Factor Authentication (MFA)
Cause
YubiKeys have certain serial numbers that may have exhibited the issue.
Solution
There is a known issue with the YubiKey with a serial number larger than 16777215 and the Personalization Tool.
For YubiKeys with serial numbers greater than 16777215:
- Under the Settings tab, ensure that Log configuration Output is set to Yubico format.
- Under Yubico OTP tap, Change the Parameter Generation Scheme to Increment Identity; Randomize Secrets - this will ensure all public identities are unique.
