diff --git a/src/calibre/ebooks/epub/split.py b/src/calibre/ebooks/epub/split.py
index 680a7e3e93..33c6360495 100644
--- a/src/calibre/ebooks/epub/split.py
+++ b/src/calibre/ebooks/epub/split.py
@@ -40,7 +40,7 @@ class Splitter(LoggingInterface):
         self.setup_cli_handler(opts.verbose)
         self.path = path
         self.always_remove = always_remove
-        self.base = os.path.splitext(path)[0] + '_split_%d.html'
+        self.base = (os.path.splitext(path)[0].replace('%', '%%') + '_split_%d.html')
         self.opts = opts
         self.orig_size = os.stat(content(path)).st_size
         self.log_info('\tSplitting %s (%d KB)', path, self.orig_size/1024.)
@@ -341,7 +341,12 @@ def split(pathtoopf, opts):
         html_files = []
         for item in opf.itermanifest():
             if 'html' in item.get('media-type', '').lower():
-                html_files.append(item.get('href').split('/')[-1])
+                f = item.get('href').split('/')[-1]
+                f2 = f.replace('&', '%26')
+                if not os.path.exists(content(f)) and os.path.exists(content(f2)):
+                    f = f2
+                    item.set('href', item.get('href').replace('&', '%26'))
+                html_files.append(f)
         changes = []
         for f in html_files:
             if os.stat(content(f)).st_size > opts.profile.flow_size:
diff --git a/src/calibre/ebooks/html.py b/src/calibre/ebooks/html.py
index 2524987d08..147e4a8a79 100644
--- a/src/calibre/ebooks/html.py
+++ b/src/calibre/ebooks/html.py
@@ -238,6 +238,13 @@ def opf_traverse(opf_reader, verbose=0, encoding=None):
             path = os.path.abspath(item.path)
             if path not in flat:
                 flat.append(path)
+    for i, path in enumerate(flat):
+        if not os.path.exists(path):
+            path = path.replace('&', '%26')
+            if os.path.exists(path):
+                flat[i] = path
+                for item in opf_reader.itermanifest():
+                    item.set('href', item.get('href').replace('&', '%26'))
     flat = [HTMLFile(path, 0, encoding, verbose) for path in flat]
     return [f for f in flat if not f.is_binary]