Private key error.

[Issa56]

A private key is a set of alphabetical and numeric numbers that are used to secure your wallet address or perform transactions on it. You have to keep your private key safe to avoid unauthorized access to your wallet address, always make sure you secure your private key at all time.

I believe the following reasons may be among the reasons why you won't be able to access your wallet address or import your wallet on another device even if you have your private key. I believe we should always avoid all of these small mistakes, which include the following:

You may have made mistakes when backing up your private key, such as using a upper case letter when you were supposed to use a lower case letter.
Some people may not notice it or may not even realize it is incorrect to use a small letter where there is a capital. If you make this mistake, you won't have access to your wallet.
Maybe you copied your private key from someplace and pasted it, but there is always space at the front, and if you don't clean it, you won't be able to make transactions or import your wallet.
I believe there are still more mistakes people do make so, if you're backing up your private key, you should be extremely cautious to avoid making blunders like these.

[bitmover]

You may have made mistakes when backing up your private key, such as using a upper case letter when you were supposed to use a lower case letter.
Some people may not notice it or may not even realize it is incorrect to use a small letter where there is a capital. If you make this mistake, you won't have access to your wallet.
Maybe you copied your private key from someplace and pasted it, but there is always space at the front, and if you don't clean it, you won't be able to make transactions or import your wallet.
I believe there are still more mistakes people do make so, if you're backing up your private key, you should be extremely cautious to avoid making blunders like these.

This is why you shouldn't be storing private keys, but Seeds.

Seeds are easier to note down and to remember. You can just note down 12-24 words. Those words are called Seed, and that seed is a masterkey which is mathemathically related to all private keys in a wallet.

Therefore, you can derive all private keys from a wallet saving only 12-24 words, which an incorrect letter (because you can easily find the mistake letter) or uppercase/lowercase (because it is case insensitive) makes no difference

From mastering bitcoin:

https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch05.asciidoc

HD Wallets (BIP-32/BIP-44)
Deterministic wallets were developed to make it easy to derive many keys from a single "seed". The most advanced form of deterministic wallets is the HD wallet defined by the BIP-32 standard. HD wallets contain keys derived in a tree structure, such that a parent key can derive a sequence of children keys, each of which can derive a sequence of grandchildren keys, and so on, to an infinite depth. This tree structure is illustrated in Type-2 HD wallet: a tree of keys generated from a single seed.


https://www.oreilly.com/library/view/mastering-bitcoin/9781491902639/ch04.html

[aysg76]

This is why you shouldn't be storing private keys, but Seeds.

Seeds are easier to note down and to remember. You can just note down 12-24 words. Those words are called Seed, and that seed is a masterkey which is mathemathically related to all private keys in a wallet.

But it must be noted that seed phrase or mnemonic codes of 12-24 words which are randomly generated must be backed up in offline modes so that nobody have access to it.Because if any other person gets to know it they will just enter the seed phrase in BIP-39 supporting wallets and the funds will be imported to that wallets and they can easily spend them.The seed phrases are randomly generated from 2048 word list or BIP-39 wordlist which you can get from GitHub link:
https://github.com/bitcoin/bips/blob/master/bip-0039/english.txt

The hacking chance are less even if the words are known because they are randomly generated in any order as there are 777,788,267,247,859,345,059,141,959,844,041,626,185 possible combinations for a 12 word seed phrase.

You must write them on piece of paper in correct order and don't post any photo or save screenshot in mobile phone as your funds safety lies with you.In most cases try to use hardware wallets like Ledger Nano S or trezor as private keys are safe on them and only transactions are shown to the blockchain but still be safe with your seeds and keys.

[nakamura12]

If you don't have a wallet you can import using seed then you should create a wallet that use seeds to store. Previously, i use mew for eth wallet and I stored my .json file that contains my private key so I created new mew wallet that use seeds then transfer my crypto to that wallet and now I am storing my wallet backing up the seeds instead of .json file or the private key which bitnover explains why. You can also do it on bitcoin wallets op.

[o_e_l_e_o]

The seed phrases are randomly generated from 2048 word list or BIP-39 wordlist

You've got this backwards. Rather than seed phrases being generated by randomly picking words, 128 bits of random entropy (in the case of 12 word seed phrases) is generated, a checksum appended, and then encoded in to very specific words from the wordlist.

The hacking chance are less even if the words are known because they are randomly generated in any order as there are 777,788,267,247,859,345,059,141,959,844,041,626,185 possible combinations for a 12 word seed phrases.

I'm not sure how you arrived at that number but it is incorrect. The actual number of valid 12 word BIP39 phrases is 2¹²⁸, or 3.4*10³⁸.

[Chikito]

You may have made mistakes when backing up your private key, such as using a upper case letter when you were supposed to use a lower case letter.

Bitcoin has a type of private key that doesn't have an upper and lower case to avoid that problem, it is called a private key in hexadecimal, for example, 810291DED5FDDEF64C74E81070842C913434812370EC1759F169631C6A6FD4E0 if you want to use it to electrum, you have to convert it first in electrum console

The hacking chance are less even if the words are known because they are randomly generated in any order as there are 777,788,267,247,859,345,059,141,959,844,041,626,185 possible combinations for a 12 word seed phrases.

I'm not sure how you arrived at that number but it is incorrect. The actual number of valid 12 word BIP39 phrases is 2¹²⁸, or 3.4*10³⁸.

maybe he got that number from order lines 2048-BIP39 word, 777 lines is word of genre, 788 is word of give and so forth.

[BlackHatCoiner]

Bitcoin has a type of private key that doesn't have an upper and lower case to avoid that problem, it is called a private key in hexadecimal, for example, 810291DED5FDDEF64C74E81070842C913434812370EC1759F169631C6A6FD4E0 if you want to use it to electrum, you have to convert it first in electrum console

Wouldn't better if you simply said that the private key is a number? That's what it is, essentially. Your computer picks a random number between a large range and translates it to either decimal, hexadecimal or WIF (for Electrum). There's no reason to define that a private key comes in a hex form; these are just different representations.

Here's an example for number 100:

Code:

Decimal: 100
Hexadecimal: 64
Binary: 1100100
WIF: KwDiBf89QgGbjEhKnhXJuH7LrciVrZi3qYjgd9M7rFU7uAq9fyDn

maybe he got that number from order lines 2048-BIP39 word, 777 lines is word of genre, 788 is word of give and so forth.

The words are supposed to be taken randomly and he mentioned a valid BIP39 seed phrase. This means that for a twelve-words seed, we get 128 bits. (11*12 = 132 - 4 bits of checksum)

[Luffygroove]

This is why wallets not only provide a Private Key to access the wallet but also in other ways. For example, MyEtherWallet has several ways to access like Mnemonic phrase, Private Key, or Keystore/JSON File aside from hardware wallets (ex: Ledger) and third parties like Metamask.

Mnemonic Phrase consists of 12 to 24 random words that are directly tied to one's private key. The Private Key consists of 64 random characters that are sensitive to upper and lower case or space like what you've mentioned. Meanwhile. Keystore/JSON File is a file that holds an encrypted version of one's private key downloaded at the beginning of wallet making.

[BlackHatCoiner]

Mnemonic Phrase consists of 12 to 24 random words that are directly tied to one's private key.

They're tied to one's master private key. We shouldn't confuse newbies; a mnemonic isn't an address' private key represented in words. It's a phrase that represents a seed, in a human-readable way, in which you can derive unlimited addresses from.

The Private Key consists of 64 random characters that are sensitive to upper and lower case or space like what you've mentioned.

If you're talking about WIF, it's always 52 characters long and they're not all randomly chosen. You should imagine a private key as 256 ones and zeroes chosen in random. (or 64 hexadecimal characters)

WIF is just another representation.

[o_e_l_e_o]

The Private Key consists of 64 random characters that are sensitive to upper and lower case or space like what you've mentioned.

If you're talking about WIF, it's always 52 characters long and they're not all randomly chosen.

Further correction:

WIF keys can be either 51 or 52 characters long. The ones which are 51 characters long are for uncompressed private keys and start with a "5". The ones which are 52 characters long are for compressed private keys and start with either a "K" or a "L". They are in Base58 and are case sensitive. The compressed keys include an extra 0x01 byte prior to the checksum, which tells your wallet software to generate the compressed public key rather than the full public key when imported.

Standard private keys are 64 characters long. They are in Base16 (hexadecimal) and are not case sensitive.

[bL4nkcode]

You may have made mistakes when backing up your private key, such as using a upper case letter when you were supposed to use a lower case letter.
Some people may not notice it or may not even realize it is incorrect to use a small letter where there is a capital. If you make this mistake, you won't have access to your wallet.

I doubt this will happen if you just copy the whole private key, not unless you manually write it either hand written or with a device's text editor/note etc.

Maybe you copied your private key from someplace and pasted it, but there is always space at the front, and if you don't clean it, you won't be able to make transactions or import your wallet.

This will only happen if you're doing lots of things and decided to backup your private keys and never check it even once. Which rarely happens given that copy-pasting either private keys or wallet address need a rechecking habit.

Rarely seen people (posting problem) having issue from their wrong backup private keys or seed, most common issue is they forget it where they save it, the device where they save has crashed/broken/lost, or they just don't know the process of importing it on the wallet (most newbies do)

[odolvlobo]

The Private Key consists of 64 random characters that are sensitive to upper and lower case or space like what you've mentioned.

If you're talking about WIF, it's always 52 characters long and they're not all randomly chosen.

Further correction:

WIF keys can be either 51 or 52 characters long. The ones which are 51 characters long are for uncompressed private keys and start with a "5". The ones which are 52 characters long are for compressed private keys and start with either a "K" or a "L". They are in Base58 and are case sensitive. The compressed keys include an extra 0x01 byte prior to the checksum, which tells your wallet software to generate the compressed public key rather than the full public key when imported.

Standard private keys are 64 characters long. They are in Base16 (hexadecimal) and are not case sensitive.

Further further correction: a private key is a number.

The number can be written in several different ways including binary (base-2), octal (base-8), decimal (base-10), hexadecimal (base-16), base-64, and WIF.

Of these methods, WIF is the most common in Bitcoin, hexadecimal is the most common in Ethereum, and base-64 is the most common most other security applications.

Also note that in hexadecimal, there is no difference between upper case A-F and lower case a-f. They both represent the same values. However, there is an extension of hexadecimal used by Ethereum that uses the case of the letters to validate the value of the private key.