How to recover Bitcoin Core wallet password

So, about 13 years ago, I got into Bitcoin through a broker who set up a wallet for me on Bitcoin Core and sent me some coins. Fast forward to now, and I’ve been trying to access that wallet, but I keep getting a message that says: "Wallet loaded successfully. The legacy wallet type is being deprecated and support for creating and opening legacy wallets will be removed in the future. Legacy wallets can be migrated to a descriptor wallet with migratewallet." When I try to migrate the wallet, it prompts me for a password, which I totally forgot. I do have the wallet.dat file, though. Does anyone know how I can get into my wallet and recover my password? Any advice would be appreciated!

I've seen this story far too many times. Brokers don't create wallets for you, brokers send your payment to the address you provide. My guess is you downloaded (or bought) a fake wallet, and now you're wasting everyone's time, including your own.

I agree. If OP willing to share list of "his" Bitcoin address that have some balance, it's probably either 1. Listed on Don't buy "wallet.dat" files with lost passwords. EXCHANGE THEM!. Note that i don't recommend anyone waste their time to inspect or crack any of those wallet.dat file. 2. Publicly known address that usually owned by exchange, hacker or presumed owned by Satoshi. And as reminder or new information to all readers, here's detailed explanation by Bitcoin Core contributor about fake wallet.

Assuming that you're telling the truth, this is still a lost cause because wallet.dat passwords aren't saved in any centralized server. Only the owner (you) knows it, not the Bitcoin developers or any Bitcoin node owner so no one can recover it for you. The only solution to this is to bruteforce the password but it will not work if you don't know the majority of its characters. Also if it's bought, you'll gonna waste your effort on it since the transactions that you're currently seeing wont match to any private key that the wallet contains once you successfully decrypt it. As for "migratewallet", it needs the password to decrypt the wallet's keys to generate output script descriptors from those that'll be imported to a new descriptor wallet.

In short, you cannot do anything with the wallet except look at the contents if you do not have the password. There is no hope of recovering the password without any additional information about it. Sorry.

I am fully in favour of anyone taking their time to reply. But, if I had a "lost money" issue, I 'd definitely not make just one post and then vanish for 3 days.

One thing that that might help you. Old bitcoin core wallets did not required passwords at beginning and many people latter added password after they have funded wallet or just decided that they want it secure.  But if you would recover wallet.dat file from old backup somewhere from time when you had no password set up than you could  access all funds on main wallets even if you encrypted it afterwards. good luck.

Good idea about looking for a possible unencrypted backup. But take note that in that case; it's only useful if the unspent transactions outputs are associated with the old unencrypted wallet's keys. The new keys that the wallet created after it's encrypted can't be recovered nor derived deterministically by the old unencrypted backup since after encryption, it set a new HDseed (for HD wallet.dat) or set a new set of keys in its keypool (for non-HD wallet.dat).