diff --git a/.appveyor.yml b/.appveyor.yml
index dbed2bde1..ec2719807 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -32,7 +32,7 @@ environment:
       RUBY: C:\Ruby25\bin
 
 install:
-  - SET PATH=%PYTHON%;%PYTHON\\Scripts;%RUBY%;%PATH%
+  - "SET PATH=%PYTHON%;%PYTHON\\Scripts;%RUBY%;%PATH%"
   - git clone -q https://github.com/iterative/oss-emulator.git
   - gem install thor builder
   - ps: cd oss-emulator