help needed with importing old wallet.dat into core 27.1

so yeah, I've got a bunch of wallet backups... most probably belong to the same wallet, but I also made some test wallets around 2012 just to mess around with. I'm on core 27.1 now and when I try to access the 2012 wallet, it throws a "wallet verification failed" error and suggests using the bitcoin-wallet tool. Do I need to go back to older versions of core for it to recognize the wallet? Is there a specific upgrade path I should follow? Like, should I run certain versions in order to eventually get it up to 27.1? Oh, and just to clarify, yes they are my wallets. Sorry if this has been answered before. If it has, just direct me to the right thread. I'm not really expecting to find any coins, but I’ve been meaning to check those backups for a while.

Why not just try this? It's installed by default with Bitcoin Core.

Is your node pruned?  If you're trying to import old wallets into a pruned node, you'll get errors.  I've never seen that particular error, however, but I don't have any wallets that old. As for the bitcoin-wallet tool, I noticed it's not include when you install QT on Windows.  It is included in the Windows Zip file, however.  You can download that from bitcoincore.org.  You'll find the bitcoin-wallet tool in the "bin" subdirectory.  Here's the help menu for the "bitcoin-wallet" tool.

You can try an older version of Bitcoin core because the format changes over time. It is possible that the "wallet.dat" you have is no longer supported or cannot be read by the most recent version of Bitcoin core. The only problem of using outdated version it carries a risk so for me, always prioritize security by running it on an offline machine and make sure you have multiple copies of your wallet.dat file before importing it to older version of core. If it still does not work, it is possible that your wallet files are corrupted. You can salvage them or dump the wallet with pywallet.

ah, explains why i couldnt find bitcoin-wallet.exe and that was it, i used the windows .exe to install core and its updates. grabbed the .zip with bitcoin-wallet and copied it out. thanks a bunch im using copies of the wallets, never the originals to play with. and it will be an offline machine with a full unpruned blockchain. all on ssd so it should go decently while scanning.