diff --git a/anki/media.py b/anki/media.py
index 6a76594af..a4ded8ca0 100644
--- a/anki/media.py
+++ b/anki/media.py
@@ -89,6 +89,10 @@ class MediaManager(object):
         return self.writeData(opath, open(opath, "rb").read())
 
     def writeData(self, opath, data):
+        if not isinstance(opath, unicode):
+            # old code/addons were passing as str
+            print "writeData() should be called with unicode"
+            opath = unicode(opath, "utf8", "ignore")
         # if fname is a full path, use only the basename
         fname = os.path.basename(opath)
         # make sure we write it in NFC form (on mac will autoconvert to NFD),