internal void AddContactRegistration(ContactRegistration reg)
{
// in practise only one registered contact is used, so remove alternatives to avoid cert
// processing picking up the wrong one
certifyManager.RemoveAllContacts();
if (certifyManager.AddRegisteredContact(reg))
{
//refresh content from vault
LoadVaultTree();
}
RaisePropertyChanged(nameof(HasRegisteredContacts));
}