diff --git a/lib/spack/spack/fetch_strategy.py b/lib/spack/spack/fetch_strategy.py
index f5425d6bbd0..5fdbaa96954 100644
--- a/lib/spack/spack/fetch_strategy.py
+++ b/lib/spack/spack/fetch_strategy.py
@@ -306,13 +306,13 @@ def fetch(self):
         content_types = re.findall(r'Content-Type:[^\r\n]+', headers,
                                    flags=re.IGNORECASE)
         if content_types and 'text/html' in content_types[-1]:
-            tty.warn("The contents of ",
-                     (self.archive_file if self.archive_file is not None
-                      else "the archive"),
-                     " look like HTML.",
-                     "The checksum will likely be bad.  If it is, you can use",
-                     "'spack clean <package>' to remove the bad archive, then",
-                     "fix your internet gateway issue and install again.")
+            msg = ("The contents of {0} look like HTML. Either the URL "
+                   "you are trying to use does not exist or you have an "
+                   "internet gateway issue. You can remove the bad archive "
+                   "using 'spack clean <package>', then try again using "
+                   "the correct URL.")
+            tty.warn(msg.format(self.archive_file or "the archive"))
+
         if save_file:
             os.rename(partial_file, save_file)