diff --git a/.appveyor.yml b/.appveyor.yml
index 7d52e34e2..6a0a6adaa 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -102,6 +102,12 @@ matrix:
 
 install:
     - "SET PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
+
+    # Temporary workaround to prevent tests failing.
+    # See GH-983 for the details.
+    # TODO remove this after tox>3.14.0 being released
+    - pip install "virtualenv>=16.0.0"
+
     - pip install tox
 
 build: false