Try to create the model only after the post_migrate signal

mayan/apps/installation/__init__.py

@@ -1,6 +1,5 @@
 from __future__ import absolute_import
 
-from django.db import transaction
 from django.db.utils import DatabaseError
 from django.dispatch import receiver
 from django.utils.translation import ugettext_lazy as _
@@ -16,18 +15,13 @@ from .links import link_menu_link, link_namespace_details, link_namespace_list
 from .models import Installation
 
 
-@receiver(post_migrate, dispatch_uid='trigger_first_time')
+@receiver(post_migrate, dispatch_uid='trigger_first_time', sender=Installation)
 def trigger_first_time(sender, **kwargs):
-    if kwargs['app'] == 'installation':
-        details, created = Installation.objects.get_or_create()
-        if created:
-            details.is_first_run = True
-            details.save()
+    Installation.objects.get_or_create()
 
 
 def check_first_run():
     try:
-        with transaction.atomic():
         details = Installation.objects.get()
     except DatabaseError:
         # Avoid database errors when the app tables haven't been created yet

mayan/apps/installation/models.py

@@ -39,7 +39,7 @@ from .literals import (FORM_SUBMIT_URL, FORM_KEY, FORM_RECEIVER_FIELD,
 class Installation(SingletonModel):
     _properties = SortedDict()
 
-    is_first_run = models.BooleanField(default=False)
+    is_first_run = models.BooleanField(default=True)
     uuid = models.CharField(max_length=48, blank=True, default=lambda: unicode(uuid.uuid4()))
 
     def add_property(self, property_instance):