diff --git a/src/borg/helpers.py b/src/borg/helpers.py
index fc1c9d001..ed6afa7f1 100644
--- a/src/borg/helpers.py
+++ b/src/borg/helpers.py
@@ -139,7 +139,7 @@ def check_extension_modules():
         raise ExtensionModuleError
     if borg.crypto.low_level.API_VERSION != '1.1_02':
         raise ExtensionModuleError
-    if platform.API_VERSION != platform.OS_API_VERSION != '1.1_03':
+    if platform.API_VERSION != platform.OS_API_VERSION or platform.API_VERSION != '1.1_03':
         raise ExtensionModuleError
     if item.API_VERSION != '1.1_02':
         raise ExtensionModuleError