diff --git a/.gitignore b/.gitignore
index 01b09d90..90ecfe9a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,7 @@
 __pycache__/
 *.py[cod]
 *$py.class
+.pytest_cache
 
 # C extensions
 *.so
diff --git a/ipwb/replay.py b/ipwb/replay.py
index 5f17f5ab..46c4b242 100755
--- a/ipwb/replay.py
+++ b/ipwb/replay.py
@@ -691,15 +691,19 @@ def handler(signum, frame):
     # respWithLinkHeader = getLinkHeaderAbbreviatedTimeMap(path, datetime)
     # resp.headers['Link'] = respWithLinkHeader.replace('\n', ' ')
 
-    if status[0] == '3':
+    if status[0] == '3' and isUri(resp.headers.get('Location')):
         # Bad assumption that the URI-M will contain \d14 but works for now.
         uriBeforeURIR = request.url[:re.search(r'/\d{14}/', request.url).end()]
         newURIM = uriBeforeURIR + resp.headers['Location']
-        resp.headers['location'] = newURIM
+        resp.headers['Location'] = newURIM
 
     return resp
 
 
+def isUri(str):
+    return re.match('^https?://', str, flags=re.IGNORECASE)
+
+
 def generateNoMementosInterface_noDatetime(urir):
     msg = '<h1>ERROR 404</h1>'
     msg += 'No capture(s) found for {0}.'.format(urir)
diff --git a/tests/test_replay.py b/tests/test_replay.py
index 6e3c4b83..45369e39 100644
--- a/tests/test_replay.py
+++ b/tests/test_replay.py
@@ -119,4 +119,45 @@ def test_unit_commandDaemon():
     except Exception as e:
         assert False
 
+
+@pytest.mark.parametrize("expected,input", [
+    (True, 'http://example.com'),
+    (True, 'https://example.com'),
+    (True, 'HTTP://EXAMPLE.COM'),
+    (True, 'HTTPS://EXAMPLE.COM'),
+    (True, 'http://example.com/'),
+    (True, 'http://example.com/foo.bar'),
+    (True, 'https://www.example.com/foo?a=b&c=d'),
+    (False, ''),
+    (False, 'foo'),
+    (False, 'foo/bar.baz'),
+    (False, 'foo?a=b&c=d'),
+    (False, '/'),
+    (False, '/foo'),
+    (False, '/foo/bar.baz'),
+    (False, '/foo?a=b&c=d'),
+    (False, './'),
+    (False, './foo'),
+    (False, './foo/bar.baz'),
+    (False, './foo?a=b&c=d'),
+    (False, '../'),
+    (False, '../foo'),
+    (False, '../foo/bar.baz'),
+    (False, '../foo?a=b&c=d'),
+    (False, '../../'),
+    (False, '../../foo'),
+    (False, '../../foo/bar.baz'),
+    (False, '../../foo?a=b&c=d'),
+    (False, 'ftp://example.com'),
+    (False, 'httpd://example.com'),
+    (False, 'http//example.com'),
+    (False, 'http:/example.com'),
+    (False, 'http:example.com'),
+    (False, 'http.example.com'),
+    (False, 'http-bin.com'),
+])
+def test_isUri(expected, input):
+    assert expected == bool(replay.isUri(input))
+
+
 # TODO: Have unit tests for each function in replay.py