Yes, except Taproot.
It needs a 'Descriptor' in Bitcoin Core and Electrum doesn't support creating/importing Taproot yet.

In Bitcoin Core, it naturally do that in a non-descriptor wallet, it will derive all three address types when you import a PrvKey.

In Electrum, you can import the same PrvKey with three different script type prefix (testnet):

And spend from the three together:

It just means that it's using the standard derivation path for BIP44 which is the first option in Electrum when selecting the script type.
"Detect Existing Accounts" should be able to find it if it had/has transactions in it.

So Electrum didn't find any transactions even though it's that wallet's seed phrase...
Please check the 'Wallet Information' of that Bitcoin Wallet with Red icon, it's in "More Option" just below the 'Backup' button.
Take note of the "Wallet Configuration (m-n)" and "Derivation Strategy".

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What version of Electrum are you using?

Also, when you restore it to Electrum, what does it show you after ticking "BIP39 seed" (below the seed phrase)?
Is it "BIP39 (checksum: ok)" or something else?
Because Electrum only unofficially supports BIP39 and it will enable you to create a wallet regardless of the seed phrase's validity.
If it is either "BIP39 (checksum: failed)" or "BIP39 (unknown wordlist)", you may have to double-check the seed phrase's words from the source itself.

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If nothing works, just follow vv181's quote about changing the 'Wallet Service URL' in his previous reply and your bitcoin(dot)com wallet should be online again.

Are you perhaps using the seed phrase of "My BCH Wallet" and "My BTC Wallet" to restore it to Electrum?
Because the one with balance is the third wallet which does not share the same seed phrase as the default wallets.

You can get its seed phrase from:

• Click the wallet. (with Red icon)
• Click the settings icon at the upper-right hand side of the wallet.
• Click "Backup", read and accept the warnings the its seed phrase will be displayed.
  
  

Use "Detect Existing Account" when restoring it to Electrum, it will work on standard derivation paths and other frequently used paths,
the fact that it didn't detected the first time means that the seed phrase you've entered has no funds in the first place.

Note: Bitcoin(dot)com wallet uses BIP44 despite it showing m/0/0 in the address path.

That note from v4.2.0 is only for the specific hardware wallet (probably a compatibility to its new firmware that supports send-to-Taproot).

But Electrum can already send to any bech32m address since v4.1.0.

Can it generate Taproot address? Not yet.
A dev said that Taproot support is in "high priority" so it may be added soon: github.com/spesmilo/electrum/issues/7544#issuecomment-1057198183

It's pretty much everything we said in the first page: the dates in your memory are off.

Another issue is you're still trying 0.3 while the version that doesn't have a word list is the initial release up to a couple of commits.
Version 0.3 is way past the version when a fixed word list is introduced so your unique seed phrase wont work there.

A fixed word list was only introduced in this commit: https://github.com/spesmilo/electrum/commit/93c27a62d47d9aab6b5502999df2ff184482e1e0 [2]
Prior to that, Electrum will ask for a 20-character-minimum "seed", or "passphrase" in the earlier commits (check my screenshot above testing the first commit)
So, you should only be trying the versions before that commit, only the last page of the commit history [1] (excluding "use random seed; do not trust the user for entropy" and earlier).

References:

• [1] First commits: github.com/spesmilo/electrum/commits/master?after=bdbd59300fbd35b01605e66145458e5f396108e8+14035 (November 5, 2011)
• [2] Mnemonic was added: github.com/spesmilo/electrum/commits/master?before=bdbd59300fbd35b01605e66145458e5f396108e8+14036 (November 8, 2011)

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Well, memory isn't all reliable IMO.
It could add or remove details based from what you've read, heard or saw.

For other wallets before 2011, I second the "Brainwallet" idea.

For that, you just have to load the wallet to Bitcoin Core and the correct balance should be displayed after it sync to the network
or if you already have a fully synced non-pruned Bitcoin Core, it only needs to be rescanned.

Even though it looked like it just generated an address whenever it needs a new one, it already has thousands pre-generated in the background which will be included to the scan.

Just for clarification, you said "qt-wallet.dat" in your post but in the title it's "wallet.dat", what's your wallet file exactly?
The former can be Bitcoin Core's wallet.

I thought you already abandoned this thread, good that you replied and inform which worked at your end.

For reference: The earlier replies like post number 5 should also work,
just right click the link to ThomasV's Pubkey in the OP then select "save as" or "save link as..." or similar option.
That will enable you to download it as ".asc" file.

Fixing Kleopatra's "lookout from server" by changing the server should also work.

I don't know how they officially labeled the version since there's no "readme" on those old commits
so I guess the version in "build.txt" are for the previous release if it wasn't updated yet.

BTW, someone already mentioned above that the "Tags" can go back to v0.1.5, if you only need the source of the releases, you can download those there.

That seems to be the previous version that you launched (v0.30) and not the alpha version.
It should ask for a passphrase before the password, plus the first version has "electrum" not "electrum.py".

I'm afraid I can't help you with the alpha version since it's not continuing nor creating the wallet in my tests either.

You can find the developers in Electrum's GitHub repository, here: github.com/spesmilo/electrum
Contributors are in "Insights->Contributors".

It still depends on the client,
although such transactions are already valid in the network, the client that will create the transaction should support bech32m for it to be able to send to a taproot address.

For example, Electrum only supported bech32m since v4.1.0 (release notes) so let's try v4.0.9:


Taproot to other address types shouldn't have any issue since a wallet that can generate a taproot address should be able to spend from it.

The alpha release used "passphrase" instead of a mnemonic.
Perhaps your invalid menmonics are actually passphrases used to generate old Electrum wallets.


See if you can run it: https://github.com/spesmilo/electrum/tree/368fa7980f74db07e22eb32edf292abeb98b8d82
(I can't create a wallet though)

If the processor had been running @10% load all day before, it'll increase its power consumption if your brute-force software bumped it to 90~100%.

I believe Bitcrack is designed to bruteforce the puzzle transaction with outputs' addresses derived from private keys of limited range.
If you want to use your CPU to something more viable, I'd suggest you to bruteforce the puzzle's unspent outputs' keys instead and limit your search space depending on the puzzle's output.

Good Luck!

Without the logs or error message, this is just going to be a guessing game.
Try starting Core with -debug=1 parameter to enable all log categories.

Perhaps it's the same as this (open) issue: Bitcoind repeatedly crashing at UpdateTip with no error message #24483?

What I explained is a possibility for all Electrum wallets created pre-v0.31 or 0.34 versions in general.
However, your situation is a bit unclear because one of your "old wallets" can't be from 2011 since it has a native SegWit address which is only became available in v3.0 (Nov 2017).

And just like all of us said, Electrum wasn't even released yet on the alleged creation date of your seed phrases.

• Here's the announcement thread: http://bitcointalk.org/index.php?topic=50936.msg607510#msg607510 (dated November 5, 2011)
• Here's the initial release (source code): github.com/spesmilo/electrum/commits/master?after=bdbd5...+14035 (dated November 5, 2011)

The first commit's "readme.txt" states "BitCoin v0.1.5 ALPHA" in the first line.

They removed readme.txt in the next few commits but still logged the version in "build.txt", but then omitted the version in the next commits.
The rest have clear version numbers and 'release' tags.

BTW, this url is better since the one that I've previously linked can't browse after 4 pages of earlier versions.
Link: github.com/bitcoin/bitcoin/commits/master?after=0817cc379f6b4c65311a682fdc7c6b204aa6a7df+34600

Okay, I suppose picture guides should beat the language barrier.

Since vv181 already provided images for the 'shortcut method', I'll provide the images for the "cmd method" instead.
It's actually shorter and easier:

• Open "Command Prompt", one of the easiest way it to use search (click search and type "cmd"):
  
• A command prompt window will open, there, type "cd C:\Program Files\Bitcoin" (change the directory if bitcoin-qt is in another folder):
  
• In the next line, type: "bitcoin-qt --reindex":
  
  
  

Wait for a few seconds and Bitcoin Core will open and it will start to reindex.

You might want to consider disabling 'prune block storage' setting since you have the space.
It will take about half of your free disk space but you can freely swap wallets and use rescan from the genesis block.
That depends on your use case.

--edit - updated image links--

For clarification, you had 10.78134 mBTC which is actually only 0.01078134 BTC, Electrum displays mBTC by default.

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Hmm... The dates are off, but at least earlier than Electrum v0.3 so this could really happen.
When restoring a funded old seed (made before v0.31 and v0.34) to the latest version, it will really result with an empty wallet due to an old "seed derivation bug".

More info here: /index.php?topic=5379817.msg58904925#msg58904925 (read page 2 to 3 for the potential solution).

That's not how to identify private key collisions, you'll have to present two different prvKeys that derive the same address.
If that how it works, then every "hacked" coins can be claimed as a collision.

And "Bitcoin Foundation" isn't some sort of a centralized body that governs Bitcoin, BTW.

Bitcoin Core v23.0 already has the necessary GUI feature to generate bech32m address, of course it supports SegWit as well.
If the wallet contains Taproot parent descriptor (the default in v23.0), there'll be a "bech32m" option in the drop-down menu in the receive tab:


Yes, the absolute fee will be cheaper for SegWit and Taproot because the virtual size of the transaction will be lower than legacy transactions,
but you still have to practice proper coin control in case you're receiving a bunch of small amounts since it's not the only factor that affects the txn's size.

Take note that Bitcoin Core is a Bitcoin full node as well so you might want to research first before deciding: Check your bandwidth and space

By adjusting your node's configuration, yes, you can accept 0-fee transactions to your own mempool.
However, when relaying that transaction to your peers, you'll see that almost all of them wont accept it.

In that scenario, only those nodes that accept 0-fee transactions will be affected by the spammer.
IMO, the damage isn't even serious because a node's mempool has a default size limit so, it won't accept any more 0-fee transactions if the limit has passed and will drop a number for any 1+ sat/vB transaction received.

Not the binaries but the old commits starting from alpha up to the latest are still available in Github.
Link: github.com/bitcoin/bitcoin/commits/master?after=178152f604aed37df703336344ff334e6d0fd244+139&branch=master
(it's the commit history so, expect a few hundreds of pages, look for "version 0.x.x release" keywords to find releases)

On that page, click "<>" to view the repository's state at that point in time.
It only starts from 0.1.5 alpha, go to satoshi.nakamotoinstitute.org/code for the first 3 (pre)releases.