diff --git a/.appveyor.yml b/.appveyor.yml
index 560d07a3d357e181d8de914b5eb52befc4f5feea..6aeaa223a77bdcade372535ba6355acc9f8c02dd 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -58,7 +58,7 @@ 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   # about it being out of date.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"
-  - "pip install --upgrade tox"
+  - "pip install --upgrade --user tox"
 
   # Install node/npm
   - ps: Install-Product node $env:8