diff --git a/.appveyor.yml b/.appveyor.yml
index 7350bc8f..9c9edd7b 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -25,7 +25,7 @@ matrix:
 # scripts that run after cloning repository
 install:
   - git clone https://github.com/google/googletest.git External/googletest
-  - update_glslang_sources.py
+  - ./update_glslang_sources.py
 
 build:
   parallel: true  # enable MSBuild parallel builds
diff --git a/.travis.yml b/.travis.yml
index 7065ee27..0237d256 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -55,7 +55,7 @@ install:
 
 before_script:
   - git clone --depth=1 https://github.com/google/googletest.git External/googletest
-  - update_glslang_sources.py
+  - ./update_glslang_sources.py
 
 script:
   - mkdir build && cd build