diff --git a/tasks.py b/tasks.py
index dfc7644..c05d200 100644
--- a/tasks.py
+++ b/tasks.py
@@ -39,8 +39,10 @@ ap.use_backend(back)
 
 MY_PERSON = ap.Person(**ME)
 
+MAX_RETRIES = 9
 
-@app.task(bind=True, max_retries=12)  # noqa: C901
+
+@app.task(bind=True, max_retries=MAX_RETRIES)  # noqa: C901
 def process_new_activity(self, iri: str) -> None:
     """Process an activity received in the inbox"""
     try:
@@ -141,7 +143,7 @@ def process_new_activity(self, iri: str) -> None:
         self.retry(exc=err, countdown=int(random.uniform(2, 4) ** self.request.retries))
 
 
-@app.task(bind=True, max_retries=12)  # noqa: C901
+@app.task(bind=True, max_retries=MAX_RETRIES)  # noqa: C901
 def fetch_og_metadata(self, iri: str) -> None:
     try:
         activity = ap.fetch_remote_activity(iri)
@@ -176,7 +178,7 @@ def fetch_og_metadata(self, iri: str) -> None:
         self.retry(exc=err, countdown=int(random.uniform(2, 4) ** self.request.retries))
 
 
-@app.task(bind=True, max_retries=12)
+@app.task(bind=True, max_retries=MAX_RETRIES)
 def cache_object(self, iri: str) -> None:
     try:
         activity = ap.fetch_remote_activity(iri)
@@ -200,7 +202,7 @@ def cache_object(self, iri: str) -> None:
         self.retry(exc=err, countdown=int(random.uniform(2, 4) ** self.request.retries))
 
 
-@app.task(bind=True, max_retries=12)
+@app.task(bind=True, max_retries=MAX_RETRIES)
 def cache_actor(self, iri: str, also_cache_attachments: bool = True) -> None:
     try:
         activity = ap.fetch_remote_activity(iri)
@@ -256,7 +258,7 @@ def cache_actor(self, iri: str, also_cache_attachments: bool = True) -> None:
         self.retry(exc=err, countdown=int(random.uniform(2, 4) ** self.request.retries))
 
 
-@app.task(bind=True, max_retries=12)
+@app.task(bind=True, max_retries=MAX_RETRIES)
 def cache_attachments(self, iri: str) -> None:
     try:
         activity = ap.fetch_remote_activity(iri)
@@ -288,7 +290,7 @@ def cache_attachments(self, iri: str) -> None:
 
         log.info(f"attachments cached for {iri}")
 
-    except (ActivityGoneError, ActivityNotFoundError):
+    except (ActivityGoneError, ActivityNotFoundError, NotAnActivityError):
         log.exception(f"dropping activity {iri}, no attachment caching")
     except Exception as err:
         log.exception(f"failed to cache attachments for {iri}")
@@ -315,7 +317,7 @@ def post_to_inbox(activity: ap.BaseActivity) -> None:
     finish_post_to_inbox.delay(activity.id)
 
 
-@app.task(bind=True, max_retries=12)  # noqa: C901
+@app.task(bind=True, max_retries=MAX_RETRIES)  # noqa: C901
 def finish_post_to_inbox(self, iri: str) -> None:
     try:
         activity = ap.fetch_remote_activity(iri)
@@ -343,7 +345,7 @@ def finish_post_to_inbox(self, iri: str) -> None:
                 back.inbox_undo_announce(MY_PERSON, obj)
             elif obj.has_type(ap.ActivityType.FOLLOW):
                 back.undo_new_follower(MY_PERSON, obj)
-    except (ActivityGoneError, ActivityNotFoundError):
+    except (ActivityGoneError, ActivityNotFoundError, NotAnActivityError):
         log.exception(f"no retry")
     except Exception as err:
         log.exception(f"failed to cache attachments for {iri}")
@@ -364,7 +366,7 @@ def post_to_outbox(activity: ap.BaseActivity) -> str:
     return activity.id
 
 
-@app.task(bind=True, max_retries=12)  # noqa:C901
+@app.task(bind=True, max_retries=MAX_RETRIES)  # noqa:C901
 def finish_post_to_outbox(self, iri: str) -> None:
     try:
         activity = ap.fetch_remote_activity(iri)
@@ -405,7 +407,7 @@ def finish_post_to_outbox(self, iri: str) -> None:
         self.retry(exc=err, countdown=int(random.uniform(2, 4) ** self.request.retries))
 
 
-@app.task(bind=True, max_retries=12)  # noqa:C901
+@app.task(bind=True, max_retries=MAX_RETRIES)  # noqa:C901
 def forward_activity(self, iri: str) -> None:
     try:
         activity = ap.fetch_remote_activity(iri)
@@ -421,7 +423,7 @@ def forward_activity(self, iri: str) -> None:
         self.retry(exc=err, countdown=int(random.uniform(2, 4) ** self.request.retries))
 
 
-@app.task(bind=True, max_retries=12)
+@app.task(bind=True, max_retries=MAX_RETRIES)
 def post_to_remote_inbox(self, payload: str, to: str) -> None:
     try:
         log.info("payload=%s", payload)