diff --git a/lib/matplotlib/__init__.py b/lib/matplotlib/__init__.py
index 8103bc3d672d..99b24483eadd 100644
--- a/lib/matplotlib/__init__.py
+++ b/lib/matplotlib/__init__.py
@@ -330,7 +330,8 @@ def impl(args, regex, min_ver=None, ignore_exit_code=False):
         # at least min_ver (if set); else, raise ExecutableNotFoundError.
         try:
             output = subprocess.check_output(
-                args, stderr=subprocess.STDOUT, universal_newlines=True)
+                args, stderr=subprocess.STDOUT,
+                universal_newlines=True, errors="replace")
         except subprocess.CalledProcessError as _cpe:
             if ignore_exit_code:
                 output = _cpe.output