Hi, We are notified that the old O365 Auth for d365 will be retired on April 2022, along with OrganizationServiceProxy class and OrganizationService class from Microsoft.Xrm.Client dll. We have a couple of application which shared a connection service class called “DomainOrganizationService”. This class extends the OrganizationService and has a lot of extended methods. Is there any class we can use to replace OrganizationService class if OrganizationService class is retired? I know there is a CrmClientService class which is recommended to use however this is a sealed class and does not allow to be extened. Otherwise do we have to have DomainOrganizationService class directly inherit IOrganizationService interface? We cannot abandon DomainOrganizationService as it is used everywhere in multiple applications and it will be a huge project to retire DomainOrganizationService class. Any help will be appreciated. Thanks