diff --git a/.appveyor.yml b/.appveyor.yml
index a59126d4e12536f492f51b300d4747585c8cd2f9..1f4796e508a79807de098836ea0dbf91d30aa7a3 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -57,7 +57,7 @@ install:
 
   # Upgrade to the latest version of pip to avoid it displaying warnings
   # about it being out of date.
-  - "pip install --disable-pip-version-check --user --upgrade pip"
+  - "python -m pip install --disable-pip-version-check --user --upgrade pip"
   - "python -m easy_install -U tox"
 
   # Install node/npm