1 files changed, 4 insertions, 2 deletions

diff --git a/lisp/url/url-http.el b/lisp/url/url-http.el
index b4d7d333f34..473da6f84c9 100644
--- a/lisp/url/url-http.el
+++ b/lisp/url/url-http.el
@@ -461,8 +461,10 @@ Return the number of characters removed."
     ;; headers, then this means that we've already tried sending
     ;; credentials to the server, and they were wrong, so just give
     ;; up.
-    (when (assoc "Authorization" url-http-extra-headers)
-      (error "Wrong authorization used for %s" url))
+    (let ((authorization (assoc "Authorization" url-http-extra-headers)))
+      (when (and authorization
+                 (not (string-match "^NTLM " (cdr authorization))))
+        (error "Wrong authorization used for %s" url)))
 
     ;; find strongest supported auth
     (dolist (this-auth auths)