GUACAMOLE-514: Slight correction to debug message.
diff --git a/src/protocols/vnc/auth.c b/src/protocols/vnc/auth.c
index 6374da5..8cc6b1d 100644
--- a/src/protocols/vnc/auth.c
+++ b/src/protocols/vnc/auth.c
@@ -45,7 +45,7 @@
     guac_client_abort(gc, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
             "Unsupported credential type requested.");
     guac_client_log(gc, GUAC_LOG_DEBUG,
-            "Unable to provided requested credential %d.",
+            "Unable to provide requested type of credential: %d.",
             credentialType);
     return NULL;