There is theoretically a way to recover lost bitcoins.
First of all, however, it is necessary to specify what is meant by “lost” bitcoins. In fact, this term does not indicate BTC that have been stolen in some way from one’s wallet, or that have been lost by trading at a loss, or that are stored on inaccessible wallets owned by third parties, but only those that are stored in a wallet. property whose private keys have been lost.
To be precise, proprietary wallets are those of which the user owns the seed or private keys.
The seed is a sequence of 12 or more words with which the same private keys can always be regenerated, regardless of the software used to do it.
The private keys instead are the long alphanumeric strings necessary to use the BTC stored on a given public address.
If access to the seed and private keys of a proprietary wallet is lost, it is no longer possible to use the BTCs stored on the public addresses associated with them. In general, wallets store these private keys on the device on which they are installed, so that they can be used without having to enter the seed each time, but if access to the wallet is lost, for example because you do not remember the access password, it is practically impossible to recover them, since they are usually saved encrypted and cannot be decrypted without the password.
Recover lost bitcoins or say goodbye forever
In theory, if you own the seed or the private keys of a wallet, it is always possible to recover access to the BTC stored in it, as long as you find the seed or the private keys. On the other hand, if both access to the wallet, any seed and private keys are lost, the BTC stored on the public addresses of the wallet can no longer be used, and must be considered as lost forever.
For this reason it is necessary to be very careful, and remember to carefully store the seed or private keys so that you can possibly recover them in case of need. However, it should also be remembered that anyone with access to that data can use the BTC stored on the wallet’s public addresses wherever they are, and with any compatible software.
That said, if bitcoins are lost in this way, what you have to do is go in search of the seed or private keys.
The first thing to do is try to remember if, and where, this data was saved.
In the event that they have not been saved, or you no longer have access to them, it is possible to check whether a wallet backup had previously been made. In fact, some wallets allow you to export a backup file that allows full recovery. However, it should be emphasized that anyone who comes into possession of that backup can recover the wallet, so if you want to do so, make sure to keep it in an ultra-safe place.
Unfortunately there are no other viable solutions: the lost bitcoins can only be recovered by restoring the wallet with the private keys of the public addresses on which they are stored, if there is a backup, or by recreating a new wallet using the restore function from seed or from private key.
For this reason, if you decide to keep your BTC on a proprietary wallet (i.e. non custodian) and not on a wallet managed by third parties, it is absolutely necessary to make sure that you have a backup of the wallet itself, or that you have the seed or private keys can be recovered.
On the other hand, however, this is not a risk-free operation, since if someone else comes into possession of this data, they can freely access the wallet, without limitations.
For these reasons, many people prefer to rely on third-party wallets (or custodians), or wallets that provide for a recovery procedure, but in this case in fact it means granting access to their BTCs also to the wallet managers.
Probably the best solution is precisely to keep the recovery data of your wallets in an ultra-secure, personal, and easily recoverable way.