Bitcoin does not offer, so far, a simple way to restore a Bitcoin wallet, so that inexperienced users do not accidentally erase their true wallet. However, there is still tricks that can be used to restore a Bitcoin wallet!
Your current wallet
: Before you restore a previous wallet that you saved
, be sure to transfer money from your current wallet if it contains Bitcoins. Because you should remember that you are about to replace it.
Replace the file wallet.dat : To restore a previous version of your wallet, you need to find the wallet.dat file in your Bitcoin software folder and replace this file with your backup copy, that you will rename wallet.dat.
Here is where you can find the wallet.dat file for each operating system:
Windows XP : %HOMEPATH%Application DataBitcoinwallet.dat
Windows Vista and Windows 7 : %HOMEPATH%AppDataRoamingBitcoinwallet.dat
Linux Ubuntu : ~/.bitcoin/wallet.dat