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Ever since .NET 2.0 System.DirectoryServices.Protocols have been a part of the framework and in .NET 3.5 even more directory related classes were added, namely System.DirectoryServices.AccountManagement. That is exactly as it sounds a namespace containing methods for account management.

This fits perfectly for a little project I have chosen to call AD Cleanup Tool. This tool will go through all accounts in a domain to clean up certain account properties, such as naming, password policy etc.

Some older solutions does not work with todays versions of Active Directory, for instance if I want to set the property User must change password at next logon. This has earlier been done by setting the property userAccountControl with the flag ADS_UF_PASSWD_CANT_CHANGE. It is not possible to set that flag anymore, but S.DS.AM gives us an even easier solution:

using(PrincipalContext context = new PrincipalContext(ContextType.Domain, "", "DC=domain,DC=com", "domain\\user", "password"))
    using(UserPrincipal userPrincipal = UserPrincipal.FindByIdentity(context, IdentityType.DistinguishedName, distinguishedName))
            userPrincipal.UserCannotChangePassword = false;
            userPrincipal.PasswordNeverExpires = false;
            return true;

S.DS.AM builds on S.DS.P, so the usage is similar to the usage of the Protocols classes. A PrincipalContext is created, in this case to the domain controller, and all actions I want to perform is made through this context. Since I only have the distinguishedName of the user above, I get a UserPrincipal using FindByIdentity().


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