diff --git a/brotli.c b/brotli.c
index 7b01007..6ed21ba 100644
--- a/brotli.c
+++ b/brotli.c
@@ -376,6 +376,7 @@ static zend_string *php_brotli_output_handler_load_dict(php_brotli_context *ctx)
 {
     char *file = BROTLI_G(output_compression_dict);
     if (!file || strlen(file) == 0) {
+        BROTLI_G(compression_coding) &= ~PHP_BROTLI_ENCODING_DCB;
         return NULL;
     }
 
@@ -392,6 +393,7 @@ static zend_string *php_brotli_output_handler_load_dict(php_brotli_context *ctx)
     if (!stream) {
         php_error_docref(NULL, E_WARNING,
                          "brotli: failed to load dictionary");
+        BROTLI_G(compression_coding) &= ~PHP_BROTLI_ENCODING_DCB;
         return NULL;
     }
 
@@ -417,6 +419,7 @@ static zend_string *php_brotli_output_handler_load_dict(php_brotli_context *ctx)
     php_stream_close(stream);
 
     if (!dict) {
+        BROTLI_G(compression_coding) &= ~PHP_BROTLI_ENCODING_DCB;
         return NULL;
     }
 
diff --git a/tests/ob_dcb_005.phpt b/tests/ob_dcb_005.phpt
new file mode 100644
index 0000000..f763c6b
--- /dev/null
+++ b/tests/ob_dcb_005.phpt
@@ -0,0 +1,26 @@
+--TEST--
+output handler: br,dcb: invalid output_compression_dict
+--SKIPIF--
+<?php
+if (BROTLI_DICTIONARY_SUPPORT === false) die('skip dictionary not supported');
+if (false === stristr(PHP_SAPI, 'cgi')) die('skip need sapi/cgi');
+?>
+--GET--
+ob=dictionary
+--ENV--
+HTTP_ACCEPT_ENCODING=br,dcb
+HTTP_AVAILABLE_DICTIONARY=:4SycXHyLhvKPL/nNaYXl60myMwris2L4X1O+q5tW1XE=:
+--FILE--
+<?php
+
+ini_set('brotli.output_compression', 1);
+ini_set('brotli.output_compression_dict', '');
+
+include(dirname(__FILE__) . '/data.inc');
+echo "{$data}";
+?>
+--EXPECT_EXTERNAL--
+files/ob_data.br
+--EXPECTHEADERS--
+Content-Encoding: br
+Vary: Accept-Encoding