diff --git a/python/src/deltachat/message.py b/python/src/deltachat/message.py
index acb1a44a0..db5185988 100644
--- a/python/src/deltachat/message.py
+++ b/python/src/deltachat/message.py
@@ -58,8 +58,6 @@ class Message(object):
 
     def set_text(self, text):
         """set text of this message. """
-        assert self.id > 0, "message not prepared"
-        assert self.is_out_preparing()
         lib.dc_msg_set_text(self._dc_msg, as_dc_charpointer(text))
 
     @props.with_doc
diff --git a/python/tests/test_account.py b/python/tests/test_account.py
index 432cdea15..88cd829cb 100644
--- a/python/tests/test_account.py
+++ b/python/tests/test_account.py
@@ -430,6 +430,30 @@ class TestOnlineAccount:
         assert self_addr not in ev[2]
         ev = ac1._evlogger.get_matching("DC_EVENT_DELETED_BLOB_FILE")
 
+    def test_prepare_file(self, acfactory, lp):
+        ac1, ac2 = acfactory.get_two_online_accounts()
+        chat = self.get_chat(ac1, ac2)
+
+        lp.sec("ac1: prepare and send attachment + text to ac2")
+        blobdir = ac1.get_blobdir()
+        p = os.path.join(blobdir, "somedata.txt")
+        with open(p, "w") as f:
+            f.write("some data")
+        msg = Message.new_empty(ac1, "file")
+        msg.set_text("hello world")
+        msg.set_file(p)
+        message = chat.prepare_message(msg)
+        assert message.is_out_preparing()
+        assert message.text == "hello world"
+        chat.send_prepared(message)
+
+        lp.sec("ac2: receive message")
+        ev = ac2._evlogger.get_matching("DC_EVENT_INCOMING_MSG|DC_EVENT_MSGS_CHANGED")
+        assert ev[2] > const.DC_CHAT_ID_LAST_SPECIAL
+        msg = ac2.get_message_by_id(ev[1])
+        assert msg.text == "hello world"
+        assert open(msg.filename).read() == "some data"
+
     def test_mvbox_sentbox_threads(self, acfactory, lp):
         lp.sec("ac1: start with mvbox thread")
         ac1 = acfactory.get_online_configuring_account(mvbox=True, sentbox=True)