diff --git a/src/calibre/ebooks/metadata/archive.py b/src/calibre/ebooks/metadata/archive.py
index 531a725c4b..daa19b6958 100644
--- a/src/calibre/ebooks/metadata/archive.py
+++ b/src/calibre/ebooks/metadata/archive.py
@@ -13,7 +13,8 @@ from calibre.customize import FileTypePlugin
 from calibre.utils.zipfile import ZipFile, stringFileHeader
 
 def is_comic(list_of_names):
-    extensions = set([x.rpartition('.')[-1].lower() for x in list_of_names])
+    extensions = set([x.rpartition('.')[-1].lower() for x in list_of_names
+                      if '.' in x and x.lower().rpartition('/')[-1] != 'thumbs.db'])
     comic_extensions = set(['jpg', 'jpeg', 'png'])
     return len(extensions - comic_extensions) == 0
 
@@ -58,7 +59,7 @@ class ArchiveExtract(FileTypePlugin):
         else:
             fnames = zf.namelist()
 
-        fnames = [x for x in fnames if '.' in x]
+        fnames = [x for x in fnames if '.' in x and x.lower().rpartition('/')[-1] != 'thumbs.db']
         if is_comic(fnames):
             ext = '.cbr' if is_rar else '.cbz'
             of = self.temporary_file('_archive_extract'+ext)