MultiBit Classic Password Rejection: Verified Credentials, Inaccessible Funds
BlockedWallet passphrase could not be recalled or recovered — access was permanently blocked.
In November 2017, a BitcoinTalk user reported a critical wallet access failure involving MultiBit Classic 0.5.15 on macOS. The user had created two encrypted wallets in late 2013 while in China, following MultiBit's recommended setup and backing up files to cloud storage.
After years of dormancy, the user reinstalled the software to initiate a transaction. Both wallets opened successfully, balances displayed correctly, and the user extracted a private key from a test wallet using a password written on paper—confirming password accuracy under conditions identical to the main wallet. However, when attempting to send Bitcoin from the larger account, MultiBit returned 'The wallet password Incorrect,' regardless of variant attempts. A recovery tool (HardCorePawn) also rejected the password.
A second user posted an identical scenario in 2021: three separately-documented MultiBit Classic wallets, each with different passwords, all rejecting authentication despite at least one password being documented as functional in 2014 transactions. That user possessed a cloned hard drive with a running MultiBit instance showing correct balances but unable to export keys or send funds. The recovery tool developer confirmed wallet files showed no corruption but dismissed the statistical improbability of three independent passwords being simultaneously wrong. The cases suggest a software bug in MultiBit Classic's password verification logic, encoding mismatch between password storage and verification, or file-format incompatibility between wallet versions.
No successful recovery was reported. The incident exposes a critical gap: legitimate owners with documented credentials, working software, and verifiable fund access could not execute transfers, trapping Bitcoin in accessible but unusable wallets.
| Stress condition | Passphrase unavailable |
| Custody system | Software wallet |
| Outcome | Blocked |
| Documentation | Present but ambiguous |
| Year observed | 2017 |
| Country | China |
Why passphrases fail years after they are set
The failure mode documented consistently across observed cases is temporal: the passphrase is set with confidence, not used for an extended period, and then cannot be reproduced exactly when needed. A single character difference — different capitalization, an added space, a slightly different special character — produces a different wallet with a zero balance. The holder may be certain they remember the passphrase while being unable to produce the exact string that was originally set.
What makes this particularly difficult is that there is no signal at the moment of failure. A wrong passphrase does not produce an error message. It opens an empty wallet. The holder sees a zero balance and typically concludes the passphrase was wrong — but without knowing which part was wrong, or by how much.
Professional passphrase recovery services can attempt permutations when the holder has partial information: they remember the general structure, typical patterns they use for passwords, the approximate length, or that it included a specific word. Recovery from total non-recollection is not feasible.
The preventive action is to store a passphrase record — not with the seed phrase, which would defeat its security purpose, but in a separate secure location accessible to the holder and potentially a designated recovery person. A passphrase that exists only in memory has a time horizon: it will eventually be forgotten, and the timing is unpredictable.