You didn't replied to my post so I guess you don't like my suspected issue...
Please at least paste the contents of "resync.cmd" file but do not launch it. (it's a script that'll automatically execute once you open it)
Right-click in it, open it as text, then paste the contents inside [code][/code] tags.

Your case isn't normal as the issues and error that you're getting aren't part of Electrum.
Like I said in my other reply, verify your executable to make sure that it's not a fake version. (instructions is in my other reply)

I'm not using that library so I can't comment on the accuracy of ChatGPT's answer or the library's performance,
but it's on the right path for using OP_Return.
I'll just reply to your other queries:

The "hostname" is the server of your choosing.
For example, if I want to connect to blockstream's public server, I'd use ('electrum.blockstream.info', port=50002, protocol='tcp')

The fee is the difference between the input(s) and output(s) values.
The "fee rate" is the fee divided by the transaction's size in "virtual bytes".

That only mean one thing, you didn't have a v1.7, "default_wallet" is for newer versions while "electrum.dat" are for old versions of Electrum.
Now, have you tried to verify the "electrum.exe" that you've been using?
Because the icon, behavior and name (if you didn't renamed it) don't look legit.

Also, do not run the suggested cmd file above it like suggested in the error msg since it may be a trap to install more viruses to your PC.
The source code doesn't have something like that nor the installer.

If you see any funded address, that doesn't mean that someone knows its private key.
That Dogecoin address is one example, someone just derived the dogecoin address from p66's address then sent dogecoins to it.

In your link, see that "Public Key Hash (Hash 160)" below the address?
That's basically the address when decoded with base58 without the network bytes and checksum.
Simply add any altcoin's network bytes, etc. and encode it with base58check to get the equivalent altcoin address.

There's a reason why ChatGPT answers are banned in multiple platforms and forums, that's on example.
I've also seen users here who referenced ChatGPT answers and some are too generic, if not, incorrect.
Give it a few more years before taking its answers into account.

I think you misunderstood the question.

Just make a copy of your "electrum.dat" file and load it to the latest version of Electrum.
That's your actual wallet file and it's still supported by version 4.3.3. (latest as of now)
Since it's a portable version, the file should be in the same folder where the portable electrum executable is located.

To load it, simply download Portable Electrum from electrum.org/#download and verify it (guide);
Open it to create the "electrum_data" folder in the same directory, leave it, open that fodler, create a wallets folder inside it then paste the copy your electrum.dat that "wallets" folder.
Go back to Electrum 4.3.3 portable and load that wallet (Choose...) instead of creating a new one, if you somehow pasted it in the wrong directory, browse manually to that dir.

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But I have one concern, the error that you get doesn't point to a valid ".cmd" file plus you said that it's v1.7 while the screenshot doesn't look like that version.
I'd suggest you to check your PC's security and verify the current version of Electrum that you're using so you wont risk the funds by running a fake version or using a compromised system.

I haven't searched but try these links.

Electrum ColdCard Plugin: https://github.com/spesmilo/electrum/blob/master/electrum/plugins/coldcard/coldcard.py#L246
ColdCard Sample Electrum Wallets (unimported): github.com/Coldcard/firmware/tree/master/docs/sample-electrum-wallets

Since he's talking about Coldcard, it's the exported .json file with simple data like keystore, script type, path, etc. which can be loaded in Electrum as a new wallet.
Using "File->Open" will import it and Electrum will then format it into a proper Electrum wallet.

Since it's P2PKH and not P2PK, it's impossible.

Even if it's from multiple coinbase transaction output,
Pay-to-Public-Key-Hash still wont show the public key until it's spent, only the PubkeyHash.
Pay-to-Public-Key on the other hand, is basically straight-out send to the public key.

Most wallets still supports generation of legacy addresses.
The question is, which wallet do you prefer?

Given the question, I guess you've tried the latest version of Electrum and found out that it only generates Native SegWit (bc1) addresses.
If so, it needs a bit of console command usage to create the type of wallet that generates legacy addresses: http://bitcointalk.org/index.php?topic=5327892.msg56694910#msg56694910

I don't know what the argument is about because a blank wallet isn't watching-only until addresses/descriptors are imported... it's blank.

I tried this and only the master public key at m/1' has BTC.
So if it's the funds that you're trying to recover, it's not a MultiSig wallet but a standard legacy wallet.

Is there more to recover than what's being shown by the second master public key?
If not, you can try these options, you can use Electrum but verify its integrity for safety: tutorial.
The options:

• option1: Recover your seed phrase in Electrum, in options, tick "BIP39 seed" Create the wallet using "legacy (p2pkh)" script type.
• option2: Do the steps in option1 but after selecting the legacy script type, edit the derivation path below from m/44'/0'/0' into: m/1'
• option3: Recover your seed phrase in Electrum, in options, tick "BIP39 seed" and "Extend this seed with custom words", type your passphrase in the next window. Create the wallet using "legacy (p2pkh)" script type.
• option4: Do the steps in option3 but after selecting the legacy script type, edit the derivation path below into: m/1'

• option5: Do the steps in option1 up until the script type window, but instead of selecting an address type, click "Detect Existing Accounts" instead (if empty repeat this with option3).

If there's a bug in the software; if not all, most of the users will experience that issue.
Only suggest to report a bug once the issue is confirmed, otherwise there'll be lots of false reports that could waste the developers' time.

Bitcoin Core's wallets can be used and generate receiving addresses even when locked.

Watching-only wallet in Bitcoin Core can produce new receiving addresses.

Note: It's best for the OP, the forum and for you if you test your hypothesis first before posting them.

His mempool will periodically drop transactions once those are included in a block.
Even if he run the node non-stop in 1.5 years, there shouldn't be any issue with his mempool.

getrawtransaction wont request from other peers, it'll either get from his mempool or his blockchain since he has txidex enabled.

You mean same as bitcoin-cli help command or bitcoincore.org/en/doc/24.0.0/rpc/blockchain/getblockchaininfo/?

AFAIK, there's none, only the list of commands and the short info about the command.
But some commands have "longer" descriptions if you used them improperly, or read those docstrings from here: github.com/spesmilo/electrum/blob/master/electrum/commands.py
This site has description of some commands but not all are covered and some examples aren't useful: bitzuma.com/posts/an-introduction-to-the-electrum-python-console/

No, Bitcoin Core's commands wont work in Electrum. Some are similar though.

For the second option, I've tested it before posting that reply.
Did "!" appear just for a split second? If so, your set transaction fee isn't enough to be a valid replacement.
It should be at least 1sat/vB higher than what is set in coinb.in; manually compute from the size and total fee to see its original "fee rate", then increase it by at least 1.

Run Electrum offline, remove the password (leave "New Password" blank) and open the wallet file as text.
The keys should be listed there under "keystore", import them by batch per wallet this time.

Note: Make sure that the text editor and your PC can handle large txt files (you managed to create that wallet so I guess you already got it covered).
Wallet file can be found here: electrum.readthedocs.io/en/latest/faq.html#where-is-my-wallet-file-located

Must be talking about 2011 version of Bitcoin Core or its wallet.dat since the article was written in 2014.
Or sometimes, users tend to use the term "wallet" when talking about "address".

But that article isn't technical for you to overthink its use of "old format", the latest version still supports the old version's keys/coins if you're worried of backwards compatibility.

Have you verified your downloaded Electrum before using it?
Because there are a lot of fake electrum.org websites that look legit.

You can follow this guide: /index.php?topic=5240594.0
But do not download the developer's PGP key from the same website, I recommend the keys in Electrum's GitHub repository: github.com/spesmilo/electrum/tree/master/pubkeys
Verify the binary that you've previously downloaded, do not redownload them or it will defeat the purpose of the verification.

This is the link to official FutureBit Apollo support thread: https://bitcointalk.org/index.php?topic=5340015.0
Check if there's a related issue and solution, if there's none, you're welcome to ask there.

Those executables aren't supposed to be double-clicked, you need to run it in a command line.
If you're using Windows, that's either your "Command Prompt" or "PoweShell".

Also, "BitCrack64.exe" is only available in the very old version, the latest only has the OpenCL and Cuda versions (go to releases for the updated binaries)
Then, use "cuBitCrack.exe" instead.