user840: I'm new to Bitcoins and I downloaded the new beta version with the encrypted wallet.  I encrypted my wallet but I have no idea on how to decrypt it.  It is locked.  How can I unlock/decrypt my wallet?
Moreover, I added a few new addresses for payments but I would like to delete some of them.  It won't allow me to delete them, however.  How can I delete addresses I never used and no longer need?  

user575: You cannot delete addresses with the standard client, however:

You can delete addresses with Pywallet.
If you never received payment with those addresses and never posted them anywhere, you can simply use them the next time you need a new address, just change their label.


user3267: 
Close Bitcoin
Find your wallet.dat
Rename to wallet.old
Start Bitcoin
Copy the address from the new empty wallet
Close Bitcoin
Rename (new) wallet.dat to wallet.new
Rename wallet.old to wallet.dat
Start Bitcoin
Send all your Bitcoins to the copied address from new wallet
Enter your password
Close Bitcoin
Rename wallet.dat to wallet.old
Rename wallet.new to wallet.dat
Start Bitcoin
Your new wallet should now be unencrypted and all old addresses gone.

This solves both your problems.

840: <p>I'm new to Bitcoins and I downloaded the new beta version with the encrypted wallet.  I encrypted my wallet but I have no idea on how to decrypt it.  It is locked.  How can I unlock/decrypt my wallet?</p>

<p>Moreover, I added a few new addresses for payments but I would like to delete some of them.  It won't allow me to delete them, however.  How can I delete addresses I never used and no longer need?  </p>
 575: <p>You cannot delete addresses with the standard client, however:</p>

<ul>
<li>You can delete addresses with <a href="https://bitcointalk.org/index.php?topic=34028.0" rel="nofollow">Pywallet</a>.</li>
<li>If you never received payment with those addresses and never posted them anywhere, you can simply use them the next time you need a new address, just change their label.</li>
</ul>
 3267: <ol>
<li>Close Bitcoin</li>
<li>Find your wallet.dat</li>
<li>Rename to wallet.old</li>
<li>Start Bitcoin</li>
<li>Copy the address from the new empty wallet</li>
<li>Close Bitcoin</li>
<li>Rename (new) wallet.dat to wallet.new</li>
<li>Rename wallet.old to wallet.dat</li>
<li>Start Bitcoin</li>
<li>Send all your Bitcoins to the copied address from new wallet</li>
<li>Enter your password</li>
<li>Close Bitcoin</li>
<li>Rename wallet.dat to wallet.old</li>
<li>Rename wallet.new to wallet.dat</li>
<li>Start Bitcoin</li>
<li>Your new wallet should now be unencrypted and all old addresses gone.</li>
</ol>

<p>This solves both your problems.</p>
