diff --git a/src/octoprint/filemanager/__init__.py b/src/octoprint/filemanager/__init__.py
index 6c27752a..1d73288b 100644
--- a/src/octoprint/filemanager/__init__.py
+++ b/src/octoprint/filemanager/__init__.py
@@ -200,9 +200,11 @@ class FileManager(object):
 					if dest_job_key in self._slicing_jobs:
 						del self._slicing_jobs[dest_job_key]
 
+		slicer = self._slicing_manager.get_slicer(slicer_name)
+
 		import time
 		start_time = time.time()
-		eventManager().fire(Events.SLICING_STARTED, {"stl": source_path, "gcode": dest_path})
+		eventManager().fire(Events.SLICING_STARTED, {"stl": source_path, "gcode": dest_path, "progressAvailable": slicer.get_slicer_properties()["progress_report"] if slicer else False})
 
 		import tempfile
 		f = tempfile.NamedTemporaryFile(suffix=".gco", delete=False)
@@ -266,10 +268,11 @@ class FileManager(object):
 	def add_file(self, destination, path, file_object, links=None, allow_overwrite=False):
 		file_path = self._storage(destination).add_file(path, file_object, links=links, allow_overwrite=allow_overwrite)
 		absolute_path = self._storage(destination).get_absolute_path(file_path)
-		file_type = get_file_type(file_path)[-1]
 
-		queue_entry = QueueEntry(file_path, file_type, destination, absolute_path)
-		self._analysis_queue.enqueue(queue_entry, high_priority=True)
+		file_type = get_file_type(absolute_path)
+		if file_type:
+			queue_entry = QueueEntry(file_path, file_type[-1], destination, absolute_path)
+			self._analysis_queue.enqueue(queue_entry, high_priority=True)
 
 		eventManager().fire(Events.UPDATED_FILES, dict(type="printables"))
 		return file_path
diff --git a/tests/filemanager/test_filemanager.py b/tests/filemanager/test_filemanager.py
index a7f1ddca..4201ac23 100644
--- a/tests/filemanager/test_filemanager.py
+++ b/tests/filemanager/test_filemanager.py
@@ -157,7 +157,7 @@ class FileManagerTest(unittest.TestCase):
 		self.file_manager.slice("some_slicer", octoprint.filemanager.FileDestinations.LOCAL, "source.file", octoprint.filemanager.FileDestinations.LOCAL, "dest.file", callback=callback, callback_args=callback_args)
 
 		# assert that events where fired
-		expected_events = [mock.call(octoprint.filemanager.Events.SLICING_STARTED, {"stl": "source.file", "gcode": "dest.file"}),
+		expected_events = [mock.call(octoprint.filemanager.Events.SLICING_STARTED, {"stl": "source.file", "gcode": "dest.file", "progressAvailable": False}),
 		                   mock.call(octoprint.filemanager.Events.SLICING_DONE, {"stl": "source.file", "gcode": "dest.file", "time": 15.694000005722046})]
 		self.fire_event.call_args_list = expected_events