diff --git a/appveyor.yml b/appveyor.yml
index 20dae4d603..56c90c622d 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -42,7 +42,7 @@ for:
     - echo>> Makefile BUILTIN_ENCOBJS=nul
     - type win32\Makefile.sub >> Makefile
     - nmake %mflags% touch-unicode-files
-    - nmake %mflags% up incs
+    - nmake %mflags% up incs UNICODE_FILES=.
     - del Makefile
     - mkdir \usr\local\bin
     - mkdir \usr\local\include
diff --git a/tool/downloader.rb b/tool/downloader.rb
index a0ef8150b2..e884056d47 100644
--- a/tool/downloader.rb
+++ b/tool/downloader.rb
@@ -85,6 +85,7 @@ class Downloader
           INDEX[:index] = IO.read index_file
         end
         file_base = File.basename(name, '.txt')
+        return if file_base == '.' # Use pre-generated headers and tables
         beta_name = INDEX[:index][/#{Regexp.quote(file_base)}(-[0-9.]+d\d+)?\.txt/]
         # make sure we always check for new versions of files,
         # because they can easily change in the beta period