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so how should I search to find the exe file so the wallet I used opens up with that wallet.dat file I found. which also leads to new Question I dont remember my wallet from 2012 had a seed some one here maybe can answer that question better. but I found the wallet but say pathway dont exist. then I searched after clicking show hidden folders. i searched word bitcoin and found the wallet.dat plus whole 9,7gb!! in that folder in appdata roaming bitcoin. thought I saw wrong cause always thought a bc wallet took 30mb!! max not 9,7GB in some file I dont understand what they are. on another HDD from almost same year I dont find a wallet.dat file but some file called crypto/crypto URL and machine key ??
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If it's "wallet.dat" and you found it with "gigs of data" in the AppData/Roaming/Bitcoin folder... then it is most likely the wallet file from "Bitcoin Core".
Firstly, make a couple of copies of "wallet.dat"... this is your "golden ticket", so you don't want to lose it.

Then, install the latest version of Bitcoin Core... Run it once... once it starts "syncing", shut it down. Then replace the
new wallet.dat in the AppData/Roaming/Bitcoin directory that it will have created with one of the copies of your
old wallet.dat and restart it again.