Windows 7 problem

if you are in win 7, go to control panel and look for user accounts. If you logged in as an administrator, you should be able to change the password there, if you know the origanal pw. If you are talking about the boot up password, that has to be cleared by changing the pin block on the mother board it self, but by doing so, it will reset the boot menu back to default.

Changing password can be done through User Accounts in control panel.
In Windows 7 :
Goto start >> control panel >>Open User Accounts and Family Safety.
Click on Change your Windows password.
Select the user to whom you want to change password.
Click on Change password
Note : you can change password for local user accounts.
You can use CTRL+ALT+DELETE to change the password for Network user

for which operating system ????

Windows XP users
Change password

1. Open Control Panel
2. Double-click the Users Accounts icon
3. Select the account you wish to change.
4. Select the option "Change my name" to change your username or "Create a password" or "Change my password" to change your password.

Note: Windows XP Home users can only change the Administrator password through Safe Mode

Windows Vista and 7 users
Change password

1. Open Control Panel
2. Click Add or remove user accounts.
3. Click the account you wish to change.
4. Click Change the password

Change username

1. Open Control Panel
2. Click Add or remove user accounts.
3. Click the account you wish to change.
4. Click Change the account name

Windows 2000 users
Change password

Microsoft Windows 2000 users can change their username by pressing CTRL + ALT + DEL while in Windows to open the Windows Security window. From this window click the "Change Password" button

Enter your old password and the new password you wish to use.
Change username

In order to change the username of an account on Windows XP you will need to have an account with Administrator rights. If you're logged in as Administrator or have an account with Administrator rights, follow the below steps.

1. Open Control Panel
2. Double-click the Users and Password icon
3. Make sure "Users must enter a user and password to use this computer" is checked.
4. Highlight the account you wish to change the username for and click the Properties button.
5. Within the Properties you'll be able to change the User name.

hope this helps

procedure. Open User Accounts in Control Panel. On the Users tab, click the name of the user whose password you want to change, and then click Reset Password. In New password and Confirm new password, type the new password, and then click OK. Notes You can change passwords only for local computer accounts, such as guest, administrator, or accounts you create for your computer. You cannot change your network logon password in User Accounts. To change your own password, press CTRL ALT DELETE and then click Change Password. My computer is not on a domain If no password has been assigned to the user's account, a password will need to be created before it can be changed. For information about creating a password, click Related Topics. The steps to perform this task differ depending on the type of user account you have. If you have a computer administrator account Open User Accounts in Control Panel. Click your account name. Click Change my password. In Type your current password, type your current password. In Type a new password and Type the new password again to confirm, type your new password. You can also enter descriptive or meaningful text in Type a word or phrase to use as a password hint to help you remember your password. Click Change Password. If you have a limited account Open User Accounts in Control Panel. Click Change my password. In Type your current password, type your current password. In Type a new password and Type the new password again to confirm, type the new password. You can also enter descriptive or meaningful text in Type a word or phrase to use as a password hint to help you remember your password. Click Change Password. Notes A user with a computer administrator account can create and change passwords for all users on the computer. Users with limited accounts can create and change their own passwords, as well as create their own password hints. If a user with a computer administrator account changes the password for another user, that user will lose all EFS-encrypted files, personal certificates, and stored passwords for Web sites or network resources. Notes To open User Accounts, click Start, click Control Panel, and then click User Accounts. For more information about user accounts, click Related Topics. Related Topics

Passwords add a level of security to your computer. When sharing a computer with others, your customized settings, computer programs, and system resources are more secure when you assign a password to your logon name or user account name. The steps to perform this task differ depending on whether your computer is a member of a network domain or is part of a workgroup (or is a stand-alone computer). My computer is on a domain You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. If your computer is connected to a network, network policy settings might also prevent you from completing this procedure. Open User Accounts in Control Panel. On the Users tab, click the name of the user whose password you want to change, and then click Reset Password. In New password and Confirm new password, type the new password, and then click OK. Notes You can change passwords only for local computer accounts, such as guest, administrator, or accounts you create for your computer. You cannot change your network logon password in User Accounts. To change your own password, press CTRL ALT DELETE and then click Change Password. My computer is not on a domain If no password has been assigned to the user's account, a password will need to be created before it can be changed. For information about creating a password, click Related Topics. The steps to perform this task differ depending on the type of user account you have. If you have a computer administrator account Open User Accounts in Control Panel. Click your account name. Click Change my password. In Type your current password, type your current password. In Type a new password and Type the new password again to confirm, type your new password. You can also enter descriptive or meaningful text in Type a word or phrase to use as a password hint to help you remember your password. Click Change Password. If you have a limited account Open User Accounts in Control Panel. Click Change my password. In Type your current password, type your current password. In Type a new password and Type the new password again to confirm, type the new password. You can also enter descriptive or meaningful text in Type a word or phrase to use as a password hint to help you remember your password. Click Change Password. Notes A user with a computer administrator account can create and change passwords for all users on the computer. Users with limited accounts can create and change their own passwords, as well as create their own password hints. If a user with a computer administrator account changes the password for another user, that user will lose all EFS-encrypted files, personal certificates, and stored passwords for Web sites or network resources. Notes To open User Accounts, click Start, click Control Panel, and then click User Accounts. For more information about user accounts, click Related Topics. Related Topics

Passwords add a level of security to your computer. When sharing a computer with others, your customized settings, computer programs, and system resources are more secure when you assign a password to your logon name or user account name. The steps to perform this task differ depending on whether your computer is a member of a network domain or is part of a workgroup (or is a stand-alone computer). My computer is on a domain You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. If your computer is connected to a network, network policy settings might also prevent you from completing this procedure. Open User Accounts in Control Panel. On the Users tab, click the name of the user whose password you want to change, and then click Reset Password. In New password and Confirm new password, type the new password, and then click OK. Notes You can change passwords only for local computer accounts, such as guest, administrator, or accounts you create for your computer. You cannot change your network logon password in User Accounts. To change your own password, press CTRL ALT DELETE and then click Change Password. My computer is not on a domain If no password has been assigned to the user's account, a password will need to be created before it can be changed. For information about creating a password, click Related Topics. The steps to perform this task differ depending on the type of user account you have. If you have a computer administrator account Open User Accounts in Control Panel. Click your account name. Click Change my password. In Type your current password, type your current password. In Type a new password and Type the new password again to confirm, type your new password. You can also enter descriptive or meaningful text in Type a word or phrase to use as a password hint to help you remember your password. Click Change Password. If you have a limited account Open User Accounts in Control Panel. Click Change my password. In Type your current password, type your current password. In Type a new password and Type the new password again to confirm, type the new password. You can also enter descriptive or meaningful text in Type a word or phrase to use as a password hint to help you remember your password. Click Change Password. Notes A user with a computer administrator account can create and change passwords for all users on the computer. Users with limited accounts can create and change their own passwords, as well as create their own password hints. If a user with a computer administrator account changes the password for another user, that user will lose all EFS-encrypted files, personal certificates, and stored passwords for Web sites or network resources. Notes To open User Accounts, click Start, click Control Panel, and then click User Accounts. For more information about user accounts, click Related Topics. Related Topics