Here are the "technicals": BIP: XX - Atomic Cross Chain Transfers | Re: Alt chains and atomic transfers

Most of those advertised "Decentralized Exchange" use something like that under that hood.
It's basically a bunch of scripts made from your own public keys that have certain conditions before each party can proceed & spend the final transaction's outputs.

That's also one of the disadvantages versus regular instant exchange because it's only compatible with coins that supports such scripts, the coin selections will be limited.
Another one (an advantage rather) is newbies normally mess-up handling their funds when it's in a non-custodial client like a decentralized exchange,
not really a disadvantage but it's a usual beginner's issue (Bec.: Beginners & Help).

Good thing that you've used you own deposit address to create that watch-only wallet.
So, what actually happened is that you have deposited your balance from Coinbase to Empire, Electrum didn't took part of that transaction.

The name clearly tells that it was created using "import bitcoin addresses or private keys" option then you pasted that address.

He will only need to backup once after he imported the keys or dumpwallet file.
After that, the 'new backup' can still generate the new/future addresses/keys as long as the hdseed is the same.
Old backups however wont contain the imported prv keys.

Better use dumpwallet on wallet1, then importwallet the dump file to wallet2.
That's doable within a minute if you're fast, minus the rescan.

You can only choose one of those software; or none, just create a bitcoin wallet (eg. Electrum) and join a Bitcoin mining pool.
Using the article in the post above, you can easily configure your miner to connect to a mining pool, then it's plug-and-play.

As long as your phone's browser supports full webpage view and connected to the same network as your Antminer, it will work (mini-browsers might not work).

Withdrawal and miner configuration will depend entirely on the pool of your choice, some have an internal account which requires you to withdraw or set an auto-withdrawal to your own wallet.
Some will automatically send your earned BTC (for a specific timeframe) to your bitcoin address.

You should post a reply to bitcoin mining pools' official threads for support because settings differ per pool (although it's already written in their respective OP).
Here are a couple of options: KanoPool | ckpool

There's no option "watch-only" in the new/restore wallet menu. Are you sure that you're using Electrum?
The two ways to create a watch-only wallet is to select "Standard->Use a master key->Paste a master public key" or "import Bitcoin addresses or private keys->Paste an address".
The difference will be the wallet type after the wallet name: [standard, watching only] and [imported, watching only], respectively.

Coinbase isn't really a wallet so you can't call it "non-watching", your receiving address still belongs to them.
They just crediting your account based form your deposits.

For the main question, you're "fucked" if you don't know where you got that address.
If you know where it came from, then you can investigate further.

You can follow BitCryptex's suggestion to remove it from your history.
If you do that, the funds from that transaction will return to your available balance because it wasn't "processed" in the first place.

To properly send a transaction, you need to directly click "send" after filling out the address, fee, amount, etc. (next version will be different)
If you have to use "preview", make sure that you will click "broadcast" after viewing the transaction's info.

Hmm, your funds that are in the Lightning Network wont be available to spend in onchain payments.
You can use it again and again for other lightning payments though, as long as you have enough incoming/outgoing liquidity.

You have to close the channel and wait for a couple of confirmations before it can be used for "regular transactions" again.
But if we reach the time when everyone is using LN, closing your channels might not be considerable since you can just send and receive BTC through LN.

---

Don't say "normal bitcoin blochchain", it's just bitcoin's blockchain or as others said: "main chain"; LN is a network, not another blockchain.

Read this topic by BitCryptex: The Lightning Network FAQ specially the part "How fast and reliable are LN payments?".
-already linked above-

In addition to those facts, if most of the micro-transactions (small payments) are done through LN,
then the mainchain will have less pending transactions that should solve those "frictions"... But it's too early to speculate that.

By breaking-down the vague parts, I think he's looking for the "invalid address" (prob 'bc1') that he used to withdraw from an exchange:

-He created a new wallet and obviously, it doesn't have balance.

-He thought by creating an invoice in the receive tab, he had 'created' and saved a new address.

@Sauaba Address aren't created and saved as you request one in the 'receive' tab.
Those are pre-generated as you created your wallet, it's just hidden by default. You can view them in the "Addresses Tab" (View->Show Addresses menu).
If you created an invoice and exit Electrum, the address that's shown in the Receive tab will use the next unused address.

You can also create multiple wallet in Electrum without deleting the others.
If the list shows a set of addresses that starts with different number/letter than your "saved address", then it's a different wallet.
Try to find if it's in your other wallet using "File->Open" menu.

The reason why bech32 address (bc1) is invalid was already answered.

Didn't watched the video but electricity must be dirt cheap in your area...
in general, it should be $10 a day for a couple of weeks, still too high but that profitability wont last long for obvious reasons.

You can ask Abdussamad (the author of your quoted post) to include it in his Electrum unofficial guide.
Or create a feature request issue in the Github repository of the official guide: https://github.com/spesmilo/electrum-docs/blob/master/index.rst

If you haven't find the links to the guides, it's in here: https://electrum.org/#documentation

1. It must be your addresses' "redeem script" since those are P2SH-P2WPKH addresses.

2. Core should keep the old addresses even after changing the hdseed (like changed passphrase, sethdseed command, etc).
Newer keys/addresses however will have an issue with old backups if the wallet had changed the hdseed after that backup.

2000 addresses will take a while to update the history and balance, is Electrum properly connected (Green circle at the lower-right?).

What do you mean "identical"? Same addresses?

You've mentioned that it's an old wallet, how old is that exactly? wallet.dat older than 2017 can't have SegWit addresses.
And you should be informed that Altcoin wallet.dat might work when imported to Bitcoin Core but obviously won't have any balance or history.

That sounds like from a person who's brainwashed by "someone" who said: "this 'forked coin' is an upgrade".

For the record, being a fork of another repository doesn't mean it's an improved version (fork-a-repo).
It's basically a copy of the original with different future developments and alterations.

There's no point in doing that since he already got the list of private keys and addresses just below the "extended private masterkey".
iancoleman's BIP39 tool will just derive the same list (change have different derivation path)
unless he changed the passphrase before which created a bunch of different set of keys/addresses.

What he need now is to find which addresses have a balance.

That's troublesome indeed...

If you do not want to check the balance using blockexplorer, then try to at least import the first few index to Electrum and see if they have a balance.
To find them, just open "find" (Windows? Ctrl+F) and search for m/0'/0'/0 then copy the private key at the start of the line,
then find m/0'/0'/1 and do the same until you collected a few of them.

Then create an imported wallet to Electrum using "Import Bitcoin addresses or private keys" and paste them like this:

Take note that Electrum might need a few seconds to sync, minutes if it's your first time using it.

You can use a Light client that doesn't require the full blockchain, eg: the popular Electrum wallet.
Just follow this to be able to export your address' private key from Armory to Electrum:


I recommend you to verify your downloaded Electrum before importing the private key to be safe,
using these instructions: https://bitcoinelectrum.com/how-to-verify-your-electrum-download/

An alternative command aside from one in the link by ETFbitcoin is dumpwallet.
Use it instead of dumpprivkey if you have more than one address that have a balance or don't know which ones have a balance.
To check their balance, simply copy an address (addr=) and paste it on a blockexplorer (https://blockstream.info/), just take note of the private keys of the ones with balance.

Don't know if this is ELI5 enough (old post of mine -edited-):

Then send them to the wallet of your choice,
If you want to use Electrum: Instead of creating an imported wallet, just create a new 'standard wallet' and sweep (Wallet->Private keys->Sweep) the keys using the same format as above.

It appears that one of your blk file is corrupted, particularly: "blk01638.dat".
Or if your disk is now full, you're out of space.

That's quite unfortunate because it must be deleted and every succeeding block files as well to be able to continue.

If you want to continue:
Shutdown Bitcoin Core, delete rev/blk01638.dat and the newer block files (not older blk), then start Bitcoin Core again.
It will re-sync starting from the blocks inside that file.

Or consider using Electrum, just make sure that you'll do everything while offline.

I'm not in the position to answer this, you should ask the man himself 

But it seems like he'd speculated that storage space will indeed become a problem regardless of Moore's Law's growth rate,
that's why that part is included in "Reclaiming Disk Space" which hints about spent transaction "pruning".
AFAIK, it wasn't implemented; according to the explanation, it is a lot different than the pruning option we have today.

It's just issued a "recan" of the blockchain for your wallet's transactions, it will not download anything if your node isn't pruned or not fully synced.
That's normal for newly loaded wallet file.

Just wait for it to finish, it could take minutes to hours depending on your PC's specs.