Help using Electrum with Blackbank's multisig

I have read the guides but I didn't make a multisig wallet since Blackbank doesn't have a key.

So this is the screen when I'm about to order Blackbank

For the public key, in Electrum I went to Wallet > Master Public Key.

Refund address: One of my receiving addresses

Private Key: Alright so in Electrum I went Wallet > Private Keys > Export, and then saved the file with the keys.

So, can I use any of these private keys to unlock escrow? BB recommends only using each once, is that right? I just want to make sure I'm doing this correctly and not wasting the vendor's time or locking up his funds, thanks for the help!


Comments


[3 Points] ThrowawayTehGay:

Technically you can, but you could potentially expose the private key as part of the transaction. If you've already used that public/private key pair then no worries - I'm sure it's fine. But for next time, or for anyone else reading this, it's actually easier and safer to generate a public/private keypair that's not linked to an actual wallet. You can use a site like bitaddress.org to randomly create the public and private keys that you need. You provide the public key to BlackBank (or whoever) and then you keep the private key somewhere safe until the transaction is finished.


[2 Points] fun-gee:

Master Public Key is different from a regular Public Key which is the thing you need.

Go to Addresses tab, select an address, Right click, select Public keys.

That number is the Public key of the selected bitcoin address. You can get the private key in the same way. This is only for Electrum 2.0 and above.

I'd also suggest to use a web service like bitaddress, brainwallet, coinb.in instead of Electrum to generate a keypair, and use that for the multisig address. If you want to use Electrum keep a separate wallet just for these signing keys. Make sure to save the private key, even though you will only need it if the market goes down or you need a refund.


[1 Points] None:

I have not used Electrum, but private key and public key should both have pairs. Is Electrum a deterministic wallet?


[1 Points] wfordthrow:

Did you ever get this working? Every time I try BB tells me "Invalid Public Key" and doesn't let me continue.