Have you tried changing the electrum server?
Try importing only the private key from the address into electrum and try sending it to the desired address.
Try downloading bitcoin core v23.0 or lower, as it has the option to create a legacy wallet, which allows you to import private keys directly.
Very happy to report that this worked! Thank you so much for taking the time to reply with such clear and comprehensive instructions! I will now redact my wallet address from earlier posts as the problem is solved.
Which one: Switching to another server, importing the private key to Electrum or Bitcoin Core?
It's important to note which solved the issue.
I tried loading from text, but the 'sign' button is greyed out:
Did you import the private key into this wallet? If so, I would expect the sign button to work. I still have no idea why Electrum can't handle this specific input normally.
Just a little explanation to what's going on:
Electrum doesn't support signing of serialized unsigned raw transaction hex, it should be a PSBT binary file or base64/base43 string for the "
Sign" button to be enabled.
Since it's hex, it assumed that the transaction is already fully signed and ready to send to the network; thus, "
Broadcast" button is enabled instead.
For the test unsigned transaction's weirdly large size, it's because Electrum created PSBT instead of unsigned raw transaction hex.
With PSBT, that large UTXO should be included to the meta data within the PSBT but that would be discarded once the transaction is fully signed and converted to serialized RAW transaction.
Now the mystery is the error which should've been reported for the developers to debug.
Or at least have the contents shared here since something "
worked" without clear explanation about how.
