diff --git a/bookwyrm/activitypub/base_activity.py b/bookwyrm/activitypub/base_activity.py
index ee4eefbdd..6ae7883ef 100644
--- a/bookwyrm/activitypub/base_activity.py
+++ b/bookwyrm/activitypub/base_activity.py
@@ -8,6 +8,10 @@ from django.db.models.fields.related_descriptors \
         import ForwardManyToOneDescriptor
 
 
+class ActivitySerializerError(ValueError):
+    ''' routine problems serializing activitypub json '''
+
+
 class ActivityEncoder(JSONEncoder):
     '''  used to convert an Activity object into json '''
     def default(self, o):
@@ -66,7 +70,8 @@ class ActivityObject:
                 value = kwargs[field.name]
             except KeyError:
                 if field.default == MISSING:
-                    raise TypeError('Missing required field: %s' % field.name)
+                    raise ActivitySerializerError(\
+                            'Missing required field: %s' % field.name)
                 value = field.default
             setattr(self, field.name, value)
 
@@ -74,7 +79,7 @@ class ActivityObject:
     def to_model(self, model, instance=None):
         ''' convert from an activity to a model instance '''
         if not isinstance(self, model.activity_serializer):
-            raise TypeError('Wrong activity type for model')
+            raise ActivitySerializerError('Wrong activity type for model')
 
         # check for an existing instance, if we're not updating a known obj
         if not instance:
@@ -136,6 +141,7 @@ def resolve_foreign_key(model, remote_id):
     ).first()
 
     if not result:
-        raise ValueError('Could not resolve remote_id in %s model: %s' % \
+        raise ActivitySerializerError(
+            'Could not resolve remote_id in %s model: %s' % \
                 (model.__name__, remote_id))
     return result
diff --git a/bookwyrm/incoming.py b/bookwyrm/incoming.py
index e9c5f6a8b..c2c223bd7 100644
--- a/bookwyrm/incoming.py
+++ b/bookwyrm/incoming.py
@@ -238,7 +238,12 @@ def handle_create(activity):
 @app.task
 def handle_delete_status(activity):
     ''' remove a status '''
-    status_id = activity['object']['id']
+    try:
+        status_id = activity['object']['id']
+    except TypeError:
+        # this isn't a great fix, because you hit this when mastadon
+        # is trying to delete a user.
+        return
     try:
         status = models.Status.objects.select_subclasses().get(
             remote_id=status_id
@@ -282,7 +287,11 @@ def handle_unfavorite(activity):
 @app.task
 def handle_boost(activity):
     ''' someone gave us a boost! '''
-    boost = activitypub.Boost(**activity).to_model(models.Boost)
+    try:
+        boost = activitypub.Boost(**activity).to_model(models.Boost)
+    except activitypub.ActivitySerializerError:
+        # this probably just means we tried to boost an unknown status
+        return
 
     if not boost.user.local:
         status_builder.create_notification(
diff --git a/bookwyrm/remote_user.py b/bookwyrm/remote_user.py
index b3408c712..9178451b4 100644
--- a/bookwyrm/remote_user.py
+++ b/bookwyrm/remote_user.py
@@ -37,10 +37,14 @@ def get_or_create_remote_user(actor):
 
 def fetch_user_data(actor):
     ''' load the user's info from the actor url '''
-    response = requests.get(
-        actor,
-        headers={'Accept': 'application/activity+json'}
-    )
+    try:
+        response = requests.get(
+            actor,
+            headers={'Accept': 'application/activity+json'}
+        )
+    except ConnectionError:
+        return None
+
     if not response.ok:
         response.raise_for_status()
     data = response.json()
@@ -83,7 +87,10 @@ def get_avatar(data):
 @app.task
 def get_remote_reviews(user_id):
     ''' ingest reviews by a new remote bookwyrm user '''
-    user = models.User.objects.get(id=user_id)
+    try:
+        user = models.User.objects.get(id=user_id)
+    except models.User.DoesNotExist:
+        return
     outbox_page = user.outbox + '?page=true'
     response = requests.get(
         outbox_page,