diff --git a/library/error.c b/library/error.c
index 608423b..e401a84 100644
--- a/library/error.c
+++ b/library/error.c
@@ -523,6 +523,8 @@
             mbedtls_snprintf( buf, buflen, "SSL - The asynchronous operation is not completed yet" );
         if( use_ret == -(MBEDTLS_ERR_SSL_EARLY_MESSAGE) )
             mbedtls_snprintf( buf, buflen, "SSL - Internal-only message signaling that a message arrived early" );
+        if( use_ret == -(MBEDTLS_ERR_SSL_UNEXPECTED_CID) )
+            mbedtls_snprintf( buf, buflen, "SSL - An encrypted DTLS-frame with an unexpected CID was received" );
         if( use_ret == -(MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS) )
             mbedtls_snprintf( buf, buflen, "SSL - A cryptographic operation is in progress. Try again later" );
 #endif /* MBEDTLS_SSL_TLS_C */