diff --git a/.appveyor.yml b/.appveyor.yml
index db0b09b0..056f67d7 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -13,7 +13,7 @@ build_script:
   - cp ci\server-cert.pem C:\
   - cp ci\server-key.pem C:\
   - cp ci\windows-ssl.cnf C:\my.cnf
-  - 'echo !include C:\my.cnf >> "C:\Program Files\MySQL\MySQL Server 5.7\my.ini"'
+  - 'echo !include C:\\my.cnf >> "C:\Program Files\MySQL\MySQL Server 5.7\my.ini"'
   - type "C:\Program Files\MySQL\MySQL Server 5.7\my.ini"
   - net stop MySQL57 && net start MySQL57
   - set PATH=C:\Program Files\MySQL\MySQL Server 5.7\bin;C:\Libraries\boost_1_71_0\lib64-msvc-14.2;C:\Libraries\boost_1_71_0\lib32-msvc-14.2;%PATH%