diff --git a/src/allmydata/scripts/tahoe_cp.py b/src/allmydata/scripts/tahoe_cp.py
index 850a1b37d..59122cfd4 100644
--- a/src/allmydata/scripts/tahoe_cp.py
+++ b/src/allmydata/scripts/tahoe_cp.py
@@ -531,7 +531,7 @@ class Copier:
                 target_is_file = False
 
         if target_is_file and target_has_trailing_slash:
-            self.to_stderr("target is not a directory, but has a slash")
+            self.to_stderr("target is not a directory, but ends with a slash")
             return 1
 
         if len(sources) > 1 and target_is_file:
diff --git a/src/allmydata/test/test_cli_cp.py b/src/allmydata/test/test_cli_cp.py
index 802227e4c..7c36b1c2f 100644
--- a/src/allmydata/test/test_cli_cp.py
+++ b/src/allmydata/test/test_cli_cp.py
@@ -919,7 +919,7 @@ class CopyOut(GridTestMixin, CLITestMixin, unittest.TestCase):
                     return set(["E5-DIRTOFILE"])
                 if err == "copying multiple things requires target be a directory":
                     return set(["E6-MANYONE"])
-                if err == "target is not a directory, but has a slash":
+                if err == "target is not a directory, but ends with a slash":
                     return set(["E7-BADSLASH"])
             self.fail("unrecognized error ('%s') %s" % (case, res))
         d.addCallback(_check)