diff --git a/allianceauth/authentication/backends.py b/allianceauth/authentication/backends.py
index f7b2038f..260dd293 100644
--- a/allianceauth/authentication/backends.py
+++ b/allianceauth/authentication/backends.py
@@ -2,7 +2,6 @@ import logging
 
 from django.contrib.auth.backends import ModelBackend
 from django.contrib.auth.models import User, Permission
-from django.contrib import messages
 
 from .models import UserProfile, CharacterOwnership, OwnershipRecord
 
@@ -41,9 +40,7 @@ class StateBackend(ModelBackend):
                 if ownership.user.profile.main_character:
                     if ownership.user.profile.main_character.character_id == token.character_id:
                         return ownership.user
-                    else:  ## this is an alt, enforce main only.
-                        if request:
-                            messages.error("Unable to authenticate with this Character, Please log in with the main character associated with this account.")
+                    else:  # this is an alt, enforce main only.
                         return None
             else:
                 logger.debug(f'{token.character_name} has changed ownership. Creating new user account.')
@@ -66,9 +63,7 @@ class StateBackend(ModelBackend):
                     user = records[0].user
                     if user.profile.main_character:
                         if user.profile.main_character.character_id != token.character_id:
-                            ## this is an alt, enforce main only due to trust issues in SSO.
-                            if request:
-                                messages.error("Unable to authenticate with this Character, Please log in with the main character associated with this account. Then add this character from the dashboard.")
+                            # this is an alt, enforce main only due to trust issues in SSO.
                             return None
 
                     token.user = user
diff --git a/allianceauth/authentication/views.py b/allianceauth/authentication/views.py
index 15c746c7..c5c036bf 100644
--- a/allianceauth/authentication/views.py
+++ b/allianceauth/authentication/views.py
@@ -171,7 +171,13 @@ def sso_login(request, token):
             request.session['registration_uid'] = user.pk
             # Go to Step 2
             return redirect('registration_register')
-    messages.error(request, _('Unable to authenticate as the selected character.'))
+    # Logging in with an alt is not allowed due to security concerns.
+    token.delete()
+    messages.error(
+        request,
+        _('Unable to authenticate as the selected character. '
+        'Please log in with the main character associated with this account.')
+    )
     return redirect(settings.LOGIN_URL)