c# changing Active Directory User PrimaryGroupID

Question

I need create Active directory user with a default PrimaryGroupID other than 513. I tried creating the account, adding the user to a group and removing the default one, but it throws an exception as "Domain Users" is the default primary group How can I accomplish this changing the PrimaryGroupID using System.DirectoryServices.AccountManagement;

Answer 1

using (var userPrincipal = UserPrincipal.FindByIdentity(Context, samsAccount))
{
var user = (DirectoryEntry) userPrincipal.GetUnderlyingObject();
DirectoryEntry adEntry = new DirectoryEntry(user.Path, "serviceUser", "Password");
var newPrimaryGroupId = 1;
user.Invoke("Put", new object[] { "primaryGroupID", newPrimaryGroupId });
user.CommitChanges();
}

Answer 2

You should:

1. Add the user to the new group.

2. Change user's primary group:

   public static void SetPrimaryGroup(string username, string groupname)
   {            
        var ctx = new PrincipalContext(ContextType.Domain);
        var group = GroupPrincipal.FindByIdentity(ctx, groupname);
        var user = UserPrincipal.FindByIdentity(ctx, username);
   
        string sid = group.Sid.Value;
        int newPrimaryGroupId = Convert.ToInt32(sid.Substring(sid.LastIndexOf('-')+1));
        var userEntry = user.GetUnderlyingObject() as DirectoryEntry;
        userEntry.Properties["primaryGroupID"].Value = newPrimaryGroupId;
        userEntry.CommitChanges();
   }
   

3. Remove the user from the old group.