diff --git a/src/calibre/utils/exim.py b/src/calibre/utils/exim.py
index 613c363da0..5595b3579e 100644
--- a/src/calibre/utils/exim.py
+++ b/src/calibre/utils/exim.py
@@ -171,7 +171,7 @@ def export(destdir, library_paths=None, dbmap=None, progress1=None, progress2=No
     if library_paths is None:
         library_paths = all_known_libraries()
     dbmap = dbmap or {}
-    dbmap = {os.path.normace(os.path.abspath(k)):v for k, v in dbmap.iteritems()}
+    dbmap = {os.path.normcase(os.path.abspath(k)):v for k, v in dbmap.iteritems()}
     exporter = Exporter(destdir)
     exporter.metadata['libraries'] = libraries = {}
     total = len(library_paths) + 1