Thanks everyone for the replies.

Pywallet seems to dump the private keys and associated addresses, so I should be OK. I found that they is a --dumpbalance flag, but it seems to timeout or not work on most of the addresses. Looks like there is about 100 or so addresses per file, so I could eventually enter them all into a web tool to check their balance. I don't want to download the entire 140GB blockchain file if at all possible, but that might be the easiest way.  Years ago I remember it took weeks to get the much smaller blockchain download because it was so slow through the peer to peer network.

Is there an easier way to download most of the blockchain file at once now? I have a 100MBPS internet connection and lots of space on an external drive, so I could go that way.

It is all rather stressful now that I realize that a screw up would be tens of thousands of dollars worth of mistakes.

Thanks again!

Hi All,

I acquired a few bitcoin back in 2012. I was using whatever version of the official bitcoin client was at this time. I did a lot of fiddling around with this bitcoin between different wallets, etc. Then I got busy and forgot about it for a few years.

I now realize that I should prepare to figure out how to sell this bitcoin. However it is currently might be worth A LOT of dollars (although I don't know how many bitcoin I have in these) so I don't want to screw this up.

What I have is:
1. A couple of unencrypted wallet.dat files (unencrypted by bitcoin, I've encrypted the files themselves with another app and stored them all over the place). I'm pretty sure they are intact.
2. JSON format dumps from pywallet for the file that I believe has the least (~2 BTC) bitcoin balance. I can presumably decrypt the other wallet.dat files and dump their contents with pywallet when I am confident in what I am doing.

The JSON format dump from one wallet.dat has what appears to be hundreds of addresses "addr" with associated info for "compressed", "hexsec", "private", "pubkey", "reserve", "sec" and "secret". Googling didn't really help me understand this much, but I did gather that the "sec" data is the unencrypted private key if it starts with 5.

Now I have no idea what to do to next get access to the bitcoin safely.

-Can I convert the wallet.dat file to a modern wallet file, preferably for a lightweight wallet like electrum?
-Will the newest official bitcoin wallet work read the old wallet.dat file?
-Can I import the JSON file into some sort of modern wallet file?
-Can I do any of these steps on an offline computer to ensure that if I make a screwup I can just start over?

Another concern I have is retaining access to the bitcoin cash version of these bitcoin as well as both versions from the upcoming fork.

-Will I loose access to bitcoin cash and the new forks depending on how I try to recover these old bitcoin files?

Any advice is hugely appreciated. I imagine that there are man others in the same boat as me.

Thank you so much.