You can use the password filter to filter domain or local account passwords. To use the password filter for domain accounts, install and register the DLL on each domain controller in the domain.

Perform the following steps to install your password filter. You can perform these steps manually, or you can write an installer to perform these steps. You need to be an Administrator or belong to the Administrator Group to perform these steps.

To install and register a password filter DLL

1. Copy the DLL to the Windows installation directory on the domain controller or local computer.

2. To register the password filter, update the following system registry key:

   HKEY_LOCAL_MACHINE
        SYSTEM
             CurrentControlSet
                  Control
                       Lsa

   If the Notification Packages subkey exists, add the name of your DLL to the existing value data. Do not overwrite the existing values, and do not include the .dll extension.

   If the Notification Packages subkey does not exist, add it, and then specify the name of the DLL for the value data. Do not include the .dll extension.

   The Notification Packages subkey can add multiple packages.

3. Find the password complexity setting.

   In Control Panel, click Performance and Maintenance, click Administrative Tools, double-click Local Security Policy, double-click Account Policies, and then double-click Password Policy.

4. To enforce both the default Windows password filter and the custom password filter, ensure that the Passwords must meet complexity requirements policy setting is enabled. Otherwise, disable the Passwords must meet complexity requirements policy setting.

See Also

Password Filter Programming Considerations
Strong Password Enforcement and Passfilt.dll
Password Filter Functions

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Build date: 2/19/2008