Windows Messenger Automatic Sign In

I have recently set up Windows Messenger on my computer.

When I signed in for the first time, I entered my hotmail email address and
password and ticked the box "Sign me in automatically"

Now everytime I start Windows Messenger it obviously signs me in
automatically.

However, on reflection and for security purposes, I would like to revert
back to having to enter my email address and password, or at least my
password, when I start Windows Messenger.

Can anyone tell me how to do this please.

I am running Windows XP Home SP2 and Windows Messenger Version 4.7.3001

I have now found out how to disable automatic sign in:-

When you click the Sign me in automatically check box when signing in to
..NET Messenger Service, your .NET Passport name and password are stored on
your computer. This allows Windows Messenger to sign you in automatically.
You can delete this information to prevent being signed in automatically.

On Windows XP Professional:

Click the Start button, click Control Panel, and then click User Accounts.
Click the Advanced tab, and then click Manage Passwords.
In Stored User Names and Passwords, click Passport.Net\*, and then click
Remove.
This does not delete your .NET Passport, but it prevents automatic sign-ins.
Click Close, and then click OK.

On Windows XP Home Edition:

Click the Start button, click Control Panel, and then click User Accounts
Click the picture that is associated with your account.
Under Related Tasks, click Manage my network passwords.
In the Stored User Names and Passwords dialog box, click
Passport.Net\*(Passport), and then click Remove.
Click OK, and then click Close.