Multiplex HD was shut down on July 26, 2017. Luckily, the Multibit HD wallet did not hold your money, and it used the BIP39 standard to create a 12-word passphrase. Coin Wallet works with this standard.
How do I restore a Multibit HD wallet?
1. You must open an existing Coin Wallet account using the 12-word passphrase from the Multibit HD in order to retrieve your bitcoins.
2. Select Bitcoin.
3. Navigate to the "Derivation path" page.
4. For P2PKH, type m/0' and click the "Save" button.
You can now spend your bitcoins. If you are still having problems, please email email@example.com to communicate with our helpful staff.