Electrum can be used to import addresses, as a standalone wallet, and it can be linked with almost any popular hardware wallet.
*steps pre wallet setup
How to Sign Messages on Electrum:
1. *Download the wallet at https://electrum.org/#download it’s compatible with linux, OSx, android, and windows. The executable file should be ~45mb
2. *Choose a standard wallet or enter the recovery mnemonic
3. Press command+a if you’re on a mac or ctrl+a if you’re on a pc to bring up the addresses section that is normally hidden on electrum
4. Press the small carrot (triangle) next to receiving aaddresses to pull up the full list.
5. Press the triangle under change addresses to pull up a list of your change addresses.
Electrum and compatible wallets are hierarchical deterministic wallets which means they are capable of creating change addresses. Change addresses are necessary because with the btc protocol only full inputs can be spent, so if you receive 100btc in address xxx and want to send 10 to address zzz your wallet will spend the full 100 and send 10 to zzz and the extra 90 to a change address that remains under your full control. This is why your receiving addresses may not hold 100% of your coins.
6. After you find the addresses that you wish to sign a message from you need to right click the address (or command click) this will bring up a list of actions one of which is “sign.”
7. After you click sign you will see 2 big boxes labeled signature and message. You will also see a smaller box in the middle labeled address which should be auto-filled with the address you’ve chosen. You need to enter the message you’d like to sign into the box and then click sign. This should fill the signature section. *Note that revealing your public address, signature, or message will not leave your bitcoins vulnerable in any way.
8. You’ve now signed a message on electrum!
*Electrum can occasionally have trouble signing messages from change addresses. and for this reason I often refer people to multibit HD. Multibit was designed by the creators of keepkey, a popular hardware wallet.
- Multibit does not have an effective way of viewing an address list so this is best done on electrum or on your keepkey chrome app (if you can do some detective work with the tx ids).
- After you download multibit you’ll get a series of messages and confirmations, once a next/finish button appears you can click it.
- On the final step of setup every time you launch multibit everything will say that it’s good to go but you'll see a synchronizing button on the bottom right, unlike electrum you do not need to wait for multibit to sync to sign messages (only to broadcast transactions).
- After you’re in go to the tools section and click on sign/verify.
- Enter your message and the address to sign from
- Click sign, and the signature box should auto fill.
- You’re done!