The wallet. dat file contains your private keys, public keys, scripts (which correspond to addresses), key metadata (e.g. labels), en.bitcoin.it
In the early days of Bitcoin, security was an afterthought. Early adopters stored their private keys in a single, unencrypted file named wallet.dat Index-of-wallet-dat
If you have found your own old wallet file and want to "index" its contents to see if there is a balance, follow these steps: 1. The "Read-Only" Rule The wallet