diff --git a/avconv_opt.c b/avconv_opt.c
index 30fbadf07a..2c43da2bbd 100644
--- a/avconv_opt.c
+++ b/avconv_opt.c
@@ -1096,6 +1096,7 @@ static OutputStream *new_attachment_stream(OptionsContext *o, AVFormatContext *o
 {
     OutputStream *ost = new_output_stream(o, oc, AVMEDIA_TYPE_ATTACHMENT);
     ost->stream_copy = 1;
+    ost->finished    = 1;
     return ost;
 }