Export wallet from multibit classic to Electrum

[dfds3]

Bitcoin Client Software and Version Number: Electrum 3.1.1, Multibit classic 0.5.19
Operating System: Windows
System Hardware Specs: N/A
Description of Problem: Can't import multibit classic keys into Electrum
Any Related Addresses: N/A
Any Related Transaction IDs: N/A
Screenshot of the problem: N/A
Log Files from the Bitcoin Client: N/A

Problem  description:

I have a bitcoin wallet with some "money" it it that was created in multibit classic.


1. I exported the private key from multibit classic to an unencrypted text file
2. I created a wallet in electrum using address from my multibit classic wallet (shows the right wallet in read only mode - which is expected)
3. When I try do sweep in electrum though.. private key doesm't work (sweep button stays grayed out)

I'm not sure if this is the problem  but I read somewhere that multibit classic uses a compressed private key and electrum uncompressed.

I'm not fixated on using Electrum as my new wallet but multiclassic is obsolete so I need to migrate to another wallet (popular one so I don't run into this issue again) so I can make a transaction. Thanks for any help


Update:
Video on how to get the sweep button to become available. I had incorrectly selected the key with the date part which was appended at to end after a space.
https://www.youtube.com/watch?v=LaijbTcxsv8w

However I still don't want to proceed with sweep because I read on this thread the following statement (I have a multibit classic key that starts with K).

"Multibit creates addresses using compressed private key, while Electrum uses uncompressed private keys. You can't decompress key - it will change public address, not allowing you to use your coins. Check first letter of your exported private key from Electrum. If first letter is K or L, it's compressed. If it's 5, you have uncompressed private key."

Has this issue been addressed? Is it safe for me to do the sweep? (don't want to lose my "money") Or do I have to do it another way?

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[RGBKey]

You should create a new Electrum wallet, one that is not based on your old private key. This new wallet will have a seed instead, which makes backing up your wallet much easier. (You should not re-use that private key from Multibit, it's poor security practice and a new Electrum wallet would be a better idea). Just go through the standard steps of creating a new Electrum wallet (File > New > etc.)

Then, follow the instructions in that video to sweep your old multibit wallet into your new Electrum wallet. You do not need to worry about compressed/uncompressed private key formats because a sweep creates a new transaction instead of importing the private key from your old multibit wallet into Electrum. Imagine taking your cash out of one wallet and placing it in another instead of carrying around both wallets.

Feel free to post any further questions

[BitMaxz]

Multibit classic is one of the old wallet and like what other said you must transfer your bitcoin to a new wallet like electrum to keep your bitcoin safe.

The youtube video is right and I think you do something wrong when you are importing your private key that is why it stays grayed out.

Try this and follow my procedure

• Open electrum wallet
• Click the file in the upper left of electrum wallet
• Click new/restore
• You can rename your wallet then next
• Choose import bitcoin addresses or private keys then next (note don't choose standard wallet like the image below.)
• Now copy the private key from your backup text of multibit classic and paste it to electrum(This time it shouldn't stay as gray just like what happened to you and don't include the timestamp just follow the video on how he copied and paste the private key.)
• And now it should be imported into your new electrum wallet.

Just for reference, the highlighted text it must be your private key.

# KEEP YOUR PRIVATE KEYS SAFE !
# Anyone who can read this file can spend your bitcoin.
#
# Format:
#   <Base58 encoded private key>[<whitespace>[<key createdAt>]]
#
#   The Base58 encoded private keys are the same format as
#   produced by the Satoshi client/ sipa dumpprivkey utility.
#
#   Key createdAt is in UTC format as specified by ISO 8601
#   e.g: 2011-12-31T16:42:00Z . The century, 'T' and 'Z' are mandatory
#
Ky2SfMwaDvgraag8QsEjBpQu529KH3J8ZgguNSuJequoJDZjjYYP 2009-10-27T22:04:57Z
# End of private keys

[HCP]

However I still don't want to proceed with sweep because I read on this thread the following statement (I have a multibit classic key that starts with K).

"Multibit creates addresses using compressed private key, while Electrum uses uncompressed private keys. You can't decompress key - it will change public address, not allowing you to use your coins. Check first letter of your exported private key from Electrum. If first letter is K or L, it's compressed. If it's 5, you have uncompressed private key."

Has this issue been addressed? Is it safe for me to do the sweep? (don't want to lose my "money") Or do I have to do it another way?

It isn't an issue... and never really was...

- If your private key starts with a "K" or "L", it is a compressed private key
- If it starts with a "5" it is an uncompressed key.

In either case, Electrum will import it just fine... (if you follow the instructions in the video and select "Import Bitcoin Addresses or private keys)... however, you are talking about "sweeping" which makes the entire point moot... as (like RGBKey mentioned), sweeping moves the coins from one wallet to another... so it doesn't really matter what type of key the source private key is... Electrum will simply create a transaction that sends from the addresses derived from those private keys, to an address in your new "standard" Electrum wallet (recommended procedure)

[dfds3]

You should create a new Electrum wallet, one that is not based on your old private key. This new wallet will have a seed instead, which makes backing up your wallet much easier. (You should not re-use that private key from Multibit, it's poor security practice and a new Electrum wallet would be a better idea). Just go through the standard steps of creating a new Electrum wallet (File > New > etc.)

Then, follow the instructions in that video to sweep your old multibit wallet into your new Electrum wallet. You do not need to worry about compressed/uncompressed private key formats because a sweep creates a new transaction instead of importing the private key from your old multibit wallet into Electrum. Imagine taking your cash out of one wallet and placing it in another instead of carrying around both wallets.

Feel free to post any further questions

(edited to add steps)

Thanks for the response.  The video is a bit different than current version of Electrum.  Can I get a bit of assistance on the exact procedure for a sweep?

1. extracted private key from multibit  (have address as well)
2. Opened up Electrum. Typed default wallet name the press next.
3.selected standard wallet then next
4. Selected create new seed then next
5. Selected standard seed type then next
6. Saved seed words then next
7. Retyped seed words then next
8. created wallet password then next
(wallet created)
9. From menu select  wallet >Private keys > sweep
10. Screen is open where its asking me for two things. "Enter private keys" and address.

Is this where I put the private key I extracted from multibit and the prior wallet address from multibit? (step 1) Or do I put the current address in the address field?

(see image below)
https://i.imgur.com/6XTQUT2.png

[dfds3]

Multibit classic is one of the old wallet and like what other said you must transfer your bitcoin to a new wallet like electrum to keep your bitcoin safe.

The youtube video is right and I think you do something wrong when you are importing your private key that is why it stays grayed out.

Try this and follow my procedure

• Open electrum wallet
• Click the file in the upper left of electrum wallet
• Click new/restore
• You can rename your wallet then next
• Choose import bitcoin addresses or private keys then next (note don't choose standard wallet like the image below.)
• Now copy the private key from your backup text of multibit classic and paste it to electrum(This time it shouldn't stay as gray just like what happened to you and don't include the timestamp just follow the video on how he copied and paste the private key.)
• And now it should be imported into your new electrum wallet.

https://bitcoinelectrum.com/files/2017/06/electrum-import-privkey-1-1.png

Just for reference, the highlighted text it must be your private key.

# KEEP YOUR PRIVATE KEYS SAFE !
# Anyone who can read this file can spend your bitcoin.
#
# Format:
#   <Base58 encoded private key>[<whitespace>[<key createdAt>]]
#
#   The Base58 encoded private keys are the same format as
#   produced by the Satoshi client/ sipa dumpprivkey utility.
#
#   Key createdAt is in UTC format as specified by ISO 8601
#   e.g: 2011-12-31T16:42:00Z . The century, 'T' and 'Z' are mandatory
#
Ky2SfMwaDvgraag8QsEjBpQu529KH3J8ZgguNSuJequoJDZjjYYP 2009-10-27T22:04:57Z
# End of private keys

What are the reasons I would chose an import over a sweep? (another poster suggested sweep is better)
 

[cissrawk]

What are the reasons I would chose an import over a sweep? (another poster suggested sweep is better)

If you choose import, your balance will stay on that(your) address. So you still use that address again.
Sweep is same as import, but moving your balance to new address that create on your wallet client for safety, just in case if someone have access to your old address.
Edit, thanks for correction

Sweep is same as import, but your balance will move to new address that create on your wallet client for safety, just in case if someone have access to your old address.

No... sweep is NOT the same as import...

- Sweep creates an on-chain transaction that moves control of the coins from one set of private keys/addresses to a completely different set of private keys/addresses
- Import does exactly that... it puts the OLD private keys/addresses into the wallet... no transaction is created, the coins don't "move" anywhere.

[HCP]

10. Screen is open where its asking me for two things. "Enter private keys" and address.

Is this where I put the private key I extracted from multibit and the prior wallet address from multibit? (step 1) Or do I put the current address in the address field?

You need to put the private keys that your extracted from MultiBit... and the address you want to SEND the coins to... ie. an address from your Electrum Wallet. By default, the address box should already be populated with the first unused "receive" address in your Electrum wallet.

What are the reasons I would chose an import over a sweep? (another poster suggested sweep is better)

If you just wanted to replicate your old MultiBit address and keep the same addresses... and/or to save on transaction fees (not such an issue at this point in time given that fees are currently super low)

Sweep is same as import, but your balance will move to new address that create on your wallet client for safety, just in case if someone have access to your old address.

No... sweep is NOT the same as import...

- Sweep creates an on-chain transaction that moves control of the coins from one set of private keys/addresses to a completely different set of private keys/addresses
- Import does exactly that... it puts the OLD private keys/addresses into the wallet... no transaction is created, the coins don't "move" anywhere.

In a "fiat banking" analogy... sweeping is like moving your money from one bank to another... importing is taking your old credit card and putting it into a new wallet.

Sweeping is considered to be the safer option, as the old keys have technically been "exposed" (displayed on screen, dumped into text file, copy/pasted via clipboard etc), so there is a chance they could be "compromised" by malware (screen grabbers, clipboard/memory copiers etc)...

[dfds3]

Worked. Thanks so much for all the help.