diff --git a/tests/common-pattern.py b/tests/common-pattern.py
--- a/tests/common-pattern.py
+++ b/tests/common-pattern.py
@@ -61,6 +61,14 @@ substitutions = [
         # FormatMessage(WSAECONNRESET)
         br'An existing connection was forcibly closed by the remote host',
     ),
+    br'$EADDRINUSE$': (
+        # strerror()
+        br'Address already in use',
+
+        # FormatMessage(WSAEADDRINUSE)
+        br'Only one usage of each socket address'
+        br' \(protocol/network address/port\) is normally permitted',
+    ),
 }
 
 for replace, msgs in _errors.items():
diff --git a/tests/test-http-bundle1.t b/tests/test-http-bundle1.t
--- a/tests/test-http-bundle1.t
+++ b/tests/test-http-bundle1.t
@@ -26,15 +26,10 @@ parts that are not bundle1/bundle2 speci
 
 Test server address cannot be reused
 
-#if windows
   $ hg serve -p $HGPORT1 2>&1
-  abort: cannot start server at 'localhost:$HGPORT1': * (glob)
+  abort: cannot start server at 'localhost:$HGPORT1': $EADDRINUSE$
   [255]
-#else
-  $ hg serve -p $HGPORT1 2>&1
-  abort: cannot start server at 'localhost:$HGPORT1': Address already in use
-  [255]
-#endif
+
   $ cd ..
   $ cat hg1.pid hg2.pid >> $DAEMON_PIDS
 
diff --git a/tests/test-http.t b/tests/test-http.t
--- a/tests/test-http.t
+++ b/tests/test-http.t
@@ -17,15 +17,10 @@
 
 Test server address cannot be reused
 
-#if windows
   $ hg serve -p $HGPORT1 2>&1
-  abort: cannot start server at 'localhost:$HGPORT1': * (glob)
+  abort: cannot start server at 'localhost:$HGPORT1': $EADDRINUSE$
   [255]
-#else
-  $ hg serve -p $HGPORT1 2>&1
-  abort: cannot start server at 'localhost:$HGPORT1': Address already in use
-  [255]
-#endif
+
   $ cd ..
   $ cat hg1.pid hg2.pid >> $DAEMON_PIDS
 
diff --git a/tests/test-https.t b/tests/test-https.t
--- a/tests/test-https.t
+++ b/tests/test-https.t
@@ -34,15 +34,10 @@ cacert not found
 
 Test server address cannot be reused
 
-#if windows
   $ hg serve -p $HGPORT --certificate=$PRIV 2>&1
-  abort: cannot start server at 'localhost:$HGPORT': * (glob)
+  abort: cannot start server at 'localhost:$HGPORT': $EADDRINUSE$
   [255]
-#else
-  $ hg serve -p $HGPORT --certificate=$PRIV 2>&1
-  abort: cannot start server at 'localhost:$HGPORT': Address already in use
-  [255]
-#endif
+
   $ cd ..
 
 Our test cert is not signed by a trusted CA. It should fail to verify if