Hello,
Putting this at the top.
TL;DR:
The OP mined bitcoins a long time ago and has a wallet.dat (actually several) that may or may not have bitcoins. Synching the block chain is very slow. The OP wants advice on what to do to retrieve his potential bitcoins in the most effective way.
I started mining in late 2011. I was using my laptop with an HD5870, if you can believe that was possible at the time. I never solved the puzzle locally after weeks of letting it run. Feeling like I was putting in resources and getting nothing, I joined a mining pool. Mining.bitcoin.cz Once I joined this, I started getting small payouts over the course of a few months. At the time, what I was getting in return wasn't much cash. This was when someone bought a pizza with bitcoins. So I really started to weigh the fact that my laptop was running at 99 deg Celsius all hours of the day and I wasn't making any real money. Eventually, the constant use of my laptop while on the charger burnt up my battery. When I ended up having to buy a new battery that was around the cost of what I made in bitcoin, I stopped mining.
I still have emails showing all my payouts to my wallet from the mining pool, which later renamed itself to Slush Pool. They show my public bitcoin address as well.
Now that bitcoin has went through the roof, I believe I'm sitting on some serious cash, ~0.5 - 1 btc. I want to try and recover this.
As I moved between PCs over the years, I copied my old drive, pasted it into my now larger drive and moved on. At some point, I would install bitcoin again, thinking I would mine, before giving up, not sure why I did this. But I ended up with another install of bitcoin on a later iteration of my machine. Finally, about a year ago I attempted to dig up my wallet. My understanding at the time was that my wallet.dat file held all my money, and all I needed to do was copy and paste my BitCoin folder with bitcoin.exe and start it up.
When I did this, and bitcoin came up I was greeted with a warning "Your Wallet is at RISK" or something of the sort. So I quickly closed the application, and researched what I could. Essentially, I found something along the lines of there was a bug in the client that would allow users who had your public address to siphon all your coins out over time. I have no idea if this is, or was, true. But rather than just launch the old bitcoin, I downloaded a new client, bitcoin-qt.exe or something like that. I copied my wallet.dat into the folder and launched it. I no longer saw the warning of my wallet at risk, but it showed 0.00 at the top for two different numbers. At the bottom, it showed 370 weeks to sync. I let this thing run for weeks thinking that it wasn't estimating it correctly, and it would eventually catch up to the chain or whatever, and find more peers. I had experience with torrents, and it's common for torrents to start out at like 0.001 kb/s while you have 1 peer and your the only other one torrenting, but slowly, more trackers become available and the torrents climb to a reasonable download rate. This never happened, in fact, after however many weeks, I distinctly remember it showing the amount of weeks not reduced by that much. So while bitcoin climbed and it was worth quite a bit, it still hadn't boomed to where it is now. So I quit.
Today, I have 3 or 4 different BitCoin wallets that came with each install, but I think I know which is the original. My issue is, I found that when I copy the wallet.dat file into an installation and run it, it doesn't just use that file, it starts creating more files in AppData. If I copy those files into my current install from older iterations of my computer, I find slightly more or less weeks to sync, but none of them show any balance in my wallet.
Finally, I think the earliest version I find is a Beta 0.8.5 client, if that helps answer my questions.
So my beginner questions, now that I've established some background. Is wallet.dat really my wallet file? Or is my wallet stored over multiple files? If my wallet shows 0.00 balance instead of 0.53 or whatever my math from my payout emails show, did I lose my BitCoin? If I lost my BitCoin is there a way to use these emails as receipts and reclaim them. I've never spent a single BitCoin a day in my life. I ran the mining client on my machine, and when I got the payout emails, at the time, my wallet did display a balance and I had transactions. What was this siphoning bug I heard about? I thought the idea behind the chain was that you always knew where the coins were going and you could track the ownership of the coin.
Also, I have heard of this "Wallet Code" some 12 word phrase that was generated for my wallet. I do not even remotely recall that being a thing back where I started, but if something came up and said "This is your secret phrase" I'm sure I wrote it down, but I looked and I cannot find it. So assume for now I don't have a wallet code or whatever that thing is.
Thanks for reading my story, here's to BitCoin. I'd appreciate any advice.
Oh, by the way, if I launch a client now with any of these wallets, the weeks to sync is in the 450 range. I don't think I have 450 weeks of running this client left in my PC. It doesn't utilize my graphics card at all, it just runs my processor at like 90-95% constantly and burns up my disc space, it starts writing new files like crazy.