diff --git a/vc_vidyo/indico_vc_vidyo/forms.py b/vc_vidyo/indico_vc_vidyo/forms.py
index 4098b73..6b0021c 100644
--- a/vc_vidyo/indico_vc_vidyo/forms.py
+++ b/vc_vidyo/indico_vc_vidyo/forms.py
@@ -21,13 +21,12 @@ from wtforms.fields.simple import TextAreaField
 from wtforms.validators import DataRequired, Length, Optional, Regexp, ValidationError
 
 from indico.modules.vc.forms import VCRoomAttachFormBase, VCRoomFormBase
-from indico.util.user import retrieve_principal
 from indico.web.forms.base import generated_data
 from indico.web.forms.fields import IndicoPasswordField, PrincipalField
 from indico.web.forms.widgets import SwitchWidget
 
 from indico_vc_vidyo import _
-from indico_vc_vidyo.util import iter_user_identities
+from indico_vc_vidyo.util import iter_user_identities, retrieve_principal
 
 
 PIN_VALIDATORS = [Optional(), Length(min=3, max=10), Regexp(r'^\d+$', message=_("The PIN must be a number"))]
@@ -71,7 +70,7 @@ class VCRoomForm(VCRoomFormBase, VidyoAdvancedFormMixin):
     def __init__(self, *args, **kwargs):
         defaults = kwargs['obj']
         if defaults.owner_user is None and defaults.owner is not None:
-            defaults.owner_user = retrieve_principal(defaults.owner, allow_groups=False, legacy=False)
+            defaults.owner_user = retrieve_principal(defaults.owner)
         super(VCRoomForm, self).__init__(*args, **kwargs)
 
     @generated_data
diff --git a/vc_vidyo/indico_vc_vidyo/plugin.py b/vc_vidyo/indico_vc_vidyo/plugin.py
index 91edbcf..b01a39d 100644
--- a/vc_vidyo/indico_vc_vidyo/plugin.py
+++ b/vc_vidyo/indico_vc_vidyo/plugin.py
@@ -31,7 +31,6 @@ from indico.modules.events.views import WPSimpleEventDisplay
 from indico.modules.vc import VCPluginMixin, VCPluginSettingsFormBase
 from indico.modules.vc.exceptions import VCRoomError, VCRoomNotFoundError
 from indico.modules.vc.views import WPVCEventPage, WPVCManageEvent
-from indico.util.user import retrieve_principal
 from indico.web.forms.fields import IndicoPasswordField
 from indico.web.forms.widgets import CKEditorWidget
 from indico.web.http_api.hooks.base import HTTPAPIHook
@@ -43,7 +42,7 @@ from indico_vc_vidyo.cli import cli
 from indico_vc_vidyo.forms import VCRoomAttachForm, VCRoomForm
 from indico_vc_vidyo.http_api import DeleteVCRoomAPI
 from indico_vc_vidyo.models.vidyo_extensions import VidyoExtension
-from indico_vc_vidyo.util import iter_extensions, iter_user_identities, update_room_from_obj
+from indico_vc_vidyo.util import iter_extensions, iter_user_identities, retrieve_principal, update_room_from_obj
 
 
 class PluginSettingsForm(VCPluginSettingsFormBase):
@@ -156,7 +155,7 @@ class VidyoPlugin(VCPluginMixin, IndicoPlugin):
         :param event: Event -- The event to the Vidyo room will be attached
         """
         client = AdminClient(self.settings)
-        owner = retrieve_principal(vc_room.data['owner'], allow_groups=False, legacy=False)
+        owner = retrieve_principal(vc_room.data['owner'])
         login_gen = iter_user_identities(owner)
         login = next(login_gen, None)
         if login is None:
@@ -232,7 +231,7 @@ class VidyoPlugin(VCPluginMixin, IndicoPlugin):
         except RoomNotFoundAPIException:
             raise VCRoomNotFoundError(_("This room has been deleted from Vidyo"))
 
-        owner = retrieve_principal(vc_room.data['owner'], allow_groups=False, legacy=False)
+        owner = retrieve_principal(vc_room.data['owner'])
         changed_owner = room_obj.ownerName not in iter_user_identities(owner)
         if changed_owner:
             login_gen = iter_user_identities(owner)
diff --git a/vc_vidyo/indico_vc_vidyo/util.py b/vc_vidyo/indico_vc_vidyo/util.py
index 756db99..14a7243 100644
--- a/vc_vidyo/indico_vc_vidyo/util.py
+++ b/vc_vidyo/indico_vc_vidyo/util.py
@@ -93,3 +93,12 @@ def update_room_from_obj(settings, vc_room, room_obj):
         'moderation_pin': room_obj.RoomMode.moderatorPIN if room_obj.RoomMode.hasModeratorPIN else "",
     })
     vc_room.vidyo_extension.extension = int(room_obj.extension)
+
+
+def retrieve_principal(principal):
+    from indico.modules.users import User
+    type_, id_ = principal
+    if type_ in {'Avatar', 'User'}:
+        return User.get(int(id_))
+    else:
+        raise ValueError('Unexpected type: {}'.format(type_))