diff --git a/Rakefile b/Rakefile
index f44946fe93739299a051de3fea84caf684e61c04..5b6f101d8ff7f59a4a6641fb5bfaff9aec21d0e4 100755
--- a/Rakefile
+++ b/Rakefile
@@ -83,7 +83,7 @@ task 'dlls' do
   env += 'EMBED_ZLIB=true '
   env += 'BUILDDIR=/tmp '
   env += "V=#{verbose} "
-  out = '/tmp/libs/opt/grpc-0.dll'
+  out = '/tmp/libs/opt/grpc-1.dll'
 
   w64 = { cross: 'x86_64-w64-mingw32', out: 'grpc_c.64.ruby' }
   w32 = { cross: 'i686-w64-mingw32', out: 'grpc_c.32.ruby' }