No. Brute-forcing a 24 word seed phrase is more difficult than brute-forcing a shamir backup with 20 words in each share.
A 24 word BIP39 seed phrase represents a 256 bits number. A shamir backup with 20 words in each share represents a 128 bits number called master secret.


I think Trezor is the only hardware wallet that supports Shamir Secret Sharing.

A 24 word seed phrase provides 256 bits of entropy and it's secure enough. Note that even a 12 word seed phrase can give you enough secuirty.
If your shamir shares have 20 words each, your master secret should give you 128 bits of entropy and that's again enough.


Take note that whether you have a wallet with a single seed phrase or a wallet with Shamir backup, it's secure enough (assuming it's generated and used in the correct way) and you should choose which one to use depending on your needs.

I personally don't like Shamir, because all shares must be generated in a single device and you need to enter all the required shares in a single device whenever you want to make a transaction and if that device is compromised, you would lose all your fund.
Shamir may be a good option if you worry about your psychical backup being stolen but can't give you extra security against hackers.


I prefer a multi-signature wallet to a wallet with shamir backup. In a multi-signature wallet, the seed phrases can be generated in separate devices and you don't have to import all of them in a single device when you want to make a transaction.

Take note that most of nodes don't have that transaction in their mempool at all and it's unlikely that the transaction can be confirmed normally.
So, there's nothing to return to the sender. The sender already has full control over the fund.

If a transaction in electrum is local, it means that it's only displayed on your device and the node you have connected to doesn't have it in its mempool.
With removing the local transaction, you remove that transaction from your wallet, so that you can make a new transaction.

o_e_l_e_o already explained what you should do very well.

Just right-click on the local transaction in electrum and select "Remove" and after that make a new transaction.

Just take note that when you close and open electrum, it's possible that you connect to a new server which has that transaction in its mempool.
If you see the unconfirmed transaction and its status is not local, right-click on that and select "Increase fee".

If you check your balance on electrum instead of using a block explorer, the only difference would be that you get the information (your balance and your transactions history) from one of electrum's servers instead of a block explorer.
If you don't select a server manually and let electrum select a server automatically, checking the balance using electrum can be even worse than using a block explorer. Because you may connect to a new node every time you open electrum.

If a user has bet very early when the time weight multiplier was at 100, his/her bet should have a weight of 200% and should get twice the a user who bet the same amount of money on France very late when the time weight multiplier was at 0.
This means that the users who bet early should make profit and the users who bet late should lose some money even if they have bet on France, since those who have bet early should get a bigger share from the prize pool.
Please correct me, if you think I am wrong. It's not fair to lose money despite betting on the winning side.

Right. With using the prefix "p2pkh:" when importing/sweeping a private key, you tell electrum that you want the legacy address.
If your address is legacy, you can also enter the private key without any prefix. That works whether the private key is uncompressed (starts with 5) or it's compressed (starts with K or L).

This will harm your privacy too.
With creating a watch-only wallet using your master public key, the owner of the node you connect to can know that all the derived addresses are owned by the same person.
If you connect to the node with your own IP address, you may even make the situation worse because the owner of the node can link all the addresses to your IP address.

Can you please be more specific on your issue? What do you exactly mean by Bitstamp not allowing withdrawals?
Do you get any errors when requesting a withdrawal? If so, what's the error message displayed? Or do you mean you don't see your balance at all when you want to make a withdrawal?

Those who have bet on France winning will get back their own fund and the house profit will come from the fund some people have bet on Namibia winning or draw.
Not all people have bet on France winning. Till now, there have been 1,434 bets on Namibia winning and 1,053 bets on draw.

Electrum's seed phrase is not case sensitive and it doesn't matter whether you use upper-case letters and or lower-case letters.
But if you have a BIP39 seed phrase and change any of the letters to an upper-case letter, you will see a message saying "BIP39 (unknown wordlist)" and you will get completely different addresses.

OP generated his/her seed phrase on another wallet and it was BIP39.

If you have the same keys in two different wallets, with just uninstalling one of them, you don't really increase your security.
OP has generated the seed phrase using HODL wallet. Even if he/she uninstalls HODL wallet and only uses electrum, nothing would change as he/she would still have the same seed phrase.
It's better to create a new wallet and move all the fund to that.

Of course, since we are talking about a wallet which holds only $25 worth of bitcoin, there's nothing to worry about.

The (v)size of data added to a transaction for each input is usually much smaller.
Even if you add a legacy input to your transaction, it adds around 140 vbytes to transaction size. Each native segwit input adds around 68 vbytes and each nested input adds around 93 vbytes to transaction size.

With having the same keys in mutliple wallets, you decrease your security as you increase the risk of getting hacked. In other words, the more wallets you import your keys in, the more attack vectors you open for hackers. That's why it's recommended to have your keys in only one wallet and avoid creating multiple wallets with the same keys.

Whether the seed phrase has been generated by electrum or it's BIP39, not all combinations of words give you valid seed phrase.

BIP39 seed phrase:
Any BIP39 seed phrase represents a 132 bits number in which the last 4 bits are checksum. In other words, the last 4 bits are a function of the first 128 bits. Therefore, if you enter 12 random words from BIP39 wordlist, there's a 15/16 chance that the combination of words doesn't pass the BIP39 checksum.

Electrum's seed phrase:
Any electrum's seed phrase is valid only if the the hash of it starts with 01, 100 or 101.
If the hash starts with 01, the seed phrase will generate legacy addresses and if the hash starts with 100, the seed phrase will generate segwit addresses. If the hash starts with 101, the seed phrase generates a 2FA wallet.


No.
A seed phrase generated by electrum provides 132 bits of entropy and a BIP39 seed phrase provides 128 bits of entropy. They give us enough randomness and security.

Oh! You are still repeating the same thing.

Take note that any bitcoin transaction you make will have a change unless you spend your UTXO(s) completely.

Assume that you have a UTXO worth 0.03 BTC and you want to spend 0.02 BTC. Your transaction must have a change worth 0.01 BTC minus fee.
The change can be sent to the address you are sending the fund from or a new address. Whether you use the same address or a new address, it doesn't make any difference to the fee you have to pay for your transactions.

Bitcoin has been always like this.


All bitcoin transactions are recorded in the blockchain and they are all available to the public.
Can you please share a transaction that has been made in those old days and can prove we are wrong?

I just installed HODL wallet to see how it works. (I had to use a phone with an old version of android, since it was not compatible with a newer version of android.)

The seed phrase generated by HODL wallet is BIP39. So, if you entered the seed phrase correctly and checked "BIP39 seed" option, it should allow you to click on "Next" button.
The error you got means that you entered the seed phrase incorrectly. Check to see if you have made any typos.

If your transaction has been flagged as RBF, you should be able to increase the fee with electrum easily.
I haven't ever used HODL wallet, but since they suggested increasing the fee using electrum, I assume it automatically flags transactions as RBF.

Did their support tell you what derivation path you should use for recovering your wallet?
I created a wallet on HODL wallet and imported the seed phrase generated by it in electrum and got different addresses.

Edit:
According to their github, HODL wallet uses the derivation path of m/0' and that's what you should enter as derivation path when recovering your wallet from seed phrase.

What version of electrum are you using on your mobile phone?
As I said in my previous post, there was a bug in the version 4.4.3 which caused the "next" button not to work when generating a new seed phrase and entering that for confirmation and that was solved in the next release.
There was no bug when entering the seed phrase for recovering the wallet.


It shouldn't be like this. You definitely did something wrong.
If you have generated two seed phrases in trustwallet, you should be able to import both of them in electrum. This is assuming you have selected "BIP39" option.


Right. That's how seed phrases generated by electrum work. There's a version number that has been encoded in electrum seed phrases and makes any seed phrase generates only one type of addresses.
Unlike an electrum's seed phrase, a BIP39 seed phrase can generate different type of addresses.

This doesn't always work.
You can know the type of an address starting with 3 with decoding a transaction made from that.
If there's no outgoing transaction from the address starting from 3, there is no way to know the address type and block explorers can't display such information about the address.

This can't be the problem. OP is probably entering a wrong seed phrase or entering a BIP39 seed phrase without selecting "BIP39" option.

The bug you are talking about appeared in the version 4.4.3 when confirming the seed phrase after generating a new one
There was no bug when entering the seed phrase for recovering the wallet.