The name "cancel transaction" is just a newbie-friendly way of labeling the actual process.
It's actually utilizing "double-spend" as indicated in the close and open brackets after the name: "Cancel (double-spend)".

Basically, it has to create another transaction that will send the funds back to one of your own wallet's address.
That's because it's really impossible to remove an already broadcast transaction from each Bitcoin node's mempool, you have to create a new transaction that will spend the same input(s) of the original unconfirmed transaction.
Since it's just another transaction, it also has a fee.

If you have been using the hard drive, that's normal. Chances that you'll recover the wallet.dat in that case is very slim.

How about the logs in "armorylog.txt"? Have you noticed some errors?

BTW, I've asked a Mod to move this to Armory sub-board.

Use dustrelayfee=n (BTC/kB) instead of the feerate-related configs | the default value is 0.00001 BTC/kB.

Here's the related note for that config:

There are no compiled binaries in the official repository, only the source code.
Which "official repository" was it downloaded from?

Home: github.com/spesmilo/electrum
Releases: github.com/spesmilo/electrum/tags

No, it's not a MultiSig wallet.
It's a standard single-sig, the online machine doesn't contain private keys, only the offline machine.
The goal is to isolate the private keys from online environment even when spending the funds.

In your case, you can just delete the offline laptop's wallet later since you won't be spending the funds for long
and use only the online watch-only wallet to receive funds and monitor the balance.
When you need to spend it, restore the offline wallet on the offline laptop to sign the transaction that you'll create using the online laptop.

I can't tell, used neither of those wallets.

The thread title's issue comes in variety of reasons.
OP's issue is seemingly a wrong block in his blockchain; in your case, check the logs (Armorylog.txt & dblog.txt) if the issue you're experiencing is the same as OP's.

For the record, it's not even mining in the first place.
All it did is to air-drop pre-mined coins to the "mobile Electroneum miners" and base the rate from the user's phone model.

Read this: electroneum101.com/what-is-electroneum
(website is not affiliated with Electroneum)

Yes.

You can remove the wallet.dat from the data directory but not individual private keys from the wallet.

Yes, it is possible to create a watching-only wallet consisting of address(es) in Bitcoin Core.
All you have to do is to create a "blank wallet" (with "disable private key" option) then import the cold-storage's address using the command: importaddress

You should use that laptop in the first place when creating the cold-storage wallet.
Then use the other online laptop for the watching-only wallet.

---

If Bitcoin Core isn't a requirement, try Electrum cold storage setup: https://electrum.readthedocs.io/en/latest/coldstorage.html
If it is, try Armory (it uses Bitcoin Core in the background):  https://www.bitcoinarmory.com/cold-storage/ (old site | refer to the link in the main page for the latest url)

Based on the previous releases, they have been consistent with the files' naming scheme except on those that needed hardware compatibility like the apk files.
So it will work, but sometime in the future, it could change.

You can actually browse to download.electrum.org using your browser to see the available files.

Is your goal to be able to simultaneously use the same wallet in Electrum and Trustwallet?
If so, you can do pooya's suggestion to do the "reverse".
If it's just to restore your Electrum wallet to Trustwallet, then sending the funds normally is the best option.

Anyway, the post that you replied to already has the answer to your question, language barrier perhaps?
Try the local boards: https://bitcointalk.org/index.php#5

It contains blocks and chainstate folder.
I tried to download the files and set-up a temporary instance of Bitcoin Core v22.0 using those files.
This instance is using the blockchain downloaded from that repo:

The blockchain loads but I can't comment nor vouch on the integrity of the files.

Now only if you really want to use it: there should be no problem if you'll just create a new wallet since it's empty;
that's assuming that the contents are legit, there's no existing wallet files in the datadir and you've set the right setting: prune=2200.
It will not work if you'll load an existing wallet.dat or will import addresses/keys because it will have to rescan to verify transactions.

But take consideration of the recommendations and warnings by other users.

The good thing is, Bitcoin Core nodes are configured to listen by default.
But usually, it's the user's network, ISP or system that's hindering inbound connections.

Electrum can create more than one wallet and open separate instances of each; Also, during the install wizard, it will ask you to create your first wallet.
You might have created a legacy wallet before you created the SegWit wallet, then mistakenly used the legacy wallet to receive the funds from Coinbase.

Unfortunately, with the address alone, it's impossible to tell where wallet it belongs to.

At least the output is still unspent so we can rule-out any case of "clipboard hijacking malware".

You can open bitcoin core if you set prune=550 (value depending on the previous setting) in your bitcoin.conf file because your current blockchain is pruned.
But that's not what you need to do to solve the main issue, it's to reindex.

If --reindex isn't convenient for you, you can just delete or rename the "blocks" and "chainstate" folders from your bitcoin data directory.
That will reset your blockchain and Bitcoin Core will redo the initial block download.

First, you need to open a channel.
It's only available for SegWit Electrum wallet (addresses start with bc1 and not a '2fa wallet'), if your wallet is of any other type, you can't.

Secondly, you need inbound capacity to be able to receive funds through lightning.
You can gain inbound capacity by sending some of your funds or by using the "swap" feature in the channels tab (it uses the same backend as the one suggested above).
The latter comes with a fee and it'll send some of your lightning funds to your on-chain funds.
You can check how much you can receive in the 'channels' tab: "can receive X. BTC".

Lastly, if the requirements above were already satisfied, use the 'Lightning' button in the receive tab instead of 'New Address'.

Yeah, I've noted in my previous reply that you're the one who spent it (in your successful attempt).

So the cold machine is set to prune the blockchain in the first place.
Then since you set the hot machine to prune too, both machine work since nothing's different in the settings and contents of the datadir.

The downside is you'll never be able to load other wallet, otherwise you'll have to re-download the blockchain.

Ah, so it's you who spent it and it's successful in your last attempt.
Congrats.

You found the reason why it needed to re-download the blockchain.
Forgot to mention that prune setting is on by default and you said that you are in default settings, so if you haven't unchecked it in the welcome screen/settings, it must be on.
That setting will delete the older blocks until the set size has reached to save disk space.

The coin that you're trying to spend was already spent (just a few minutes ago): f6191eb2d49ae95ad4ca329aa928bc6eec625e95a668ff01b5e138cd6c460e54:0

If the file above doesn't work, get the 32-bit Windows binaries from the outdated armory website bitcoinarmory.com (but from its older version)

Link: https://web.archive.org/web/20130917140922/http://bitcoinarmory.com/download/ (click Windows icon, then "code.google.com download page").
It will redirect you to this archived page: https://web.archive.org/web/20130814045236/http://code.google.com/p/bitcoinarmory/downloads/list
The download links there are still working but it's archived by a third-party so I can't comment on the integrity of the files.