diff --git a/crypto/block.c b/crypto/block.c
index be823ee..64c8420 100644
--- a/crypto/block.c
+++ b/crypto/block.c
@@ -59,7 +59,8 @@ QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options,
 
     if (options->format >= G_N_ELEMENTS(qcrypto_block_drivers) ||
         !qcrypto_block_drivers[options->format]) {
-        error_setg(errp, "Unsupported block driver %d", options->format);
+        error_setg(errp, "Unsupported block driver %s",
+                   QCryptoBlockFormat_lookup[options->format]);
         g_free(block);
         return NULL;
     }
@@ -88,7 +89,8 @@ QCryptoBlock *qcrypto_block_create(QCryptoBlockCreateOptions *options,
 
     if (options->format >= G_N_ELEMENTS(qcrypto_block_drivers) ||
         !qcrypto_block_drivers[options->format]) {
-        error_setg(errp, "Unsupported block driver %d", options->format);
+        error_setg(errp, "Unsupported block driver %s",
+                   QCryptoBlockFormat_lookup[options->format]);
         g_free(block);
         return NULL;
     }
diff --git a/crypto/cipher-builtin.c b/crypto/cipher-builtin.c
index 88963f6..9d25842 100644
--- a/crypto/cipher-builtin.c
+++ b/crypto/cipher-builtin.c
@@ -244,7 +244,8 @@ static int qcrypto_cipher_init_aes(QCryptoCipher *cipher,
     if (cipher->mode != QCRYPTO_CIPHER_MODE_CBC &&
         cipher->mode != QCRYPTO_CIPHER_MODE_ECB &&
         cipher->mode != QCRYPTO_CIPHER_MODE_XTS) {
-        error_setg(errp, "Unsupported cipher mode %d", cipher->mode);
+        error_setg(errp, "Unsupported cipher mode %s",
+                   QCryptoCipherMode_lookup[cipher->mode]);
         return -1;
     }
 
@@ -376,7 +377,8 @@ static int qcrypto_cipher_init_des_rfb(QCryptoCipher *cipher,
     QCryptoCipherBuiltin *ctxt;
 
     if (cipher->mode != QCRYPTO_CIPHER_MODE_ECB) {
-        error_setg(errp, "Unsupported cipher mode %d", cipher->mode);
+        error_setg(errp, "Unsupported cipher mode %s",
+                   QCryptoCipherMode_lookup[cipher->mode]);
         return -1;
     }
 
@@ -442,7 +444,8 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         break;
     default:
         error_setg(errp,
-                   "Unsupported cipher algorithm %d", cipher->alg);
+                   "Unsupported cipher algorithm %s",
+                   QCryptoCipherAlgorithm_lookup[cipher->alg]);
         goto error;
     }
 
diff --git a/crypto/cipher-gcrypt.c b/crypto/cipher-gcrypt.c
index 3652aa1..da3f4c7 100644
--- a/crypto/cipher-gcrypt.c
+++ b/crypto/cipher-gcrypt.c
@@ -70,7 +70,8 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         gcrymode = GCRY_CIPHER_MODE_CBC;
         break;
     default:
-        error_setg(errp, "Unsupported cipher mode %d", mode);
+        error_setg(errp, "Unsupported cipher mode %s",
+                   QCryptoCipherMode_lookup[mode]);
         return NULL;
     }
 
@@ -120,7 +121,8 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         break;
 
     default:
-        error_setg(errp, "Unsupported cipher algorithm %d", alg);
+        error_setg(errp, "Unsupported cipher algorithm %s",
+                   QCryptoCipherAlgorithm_lookup[alg]);
         return NULL;
     }
 
diff --git a/crypto/cipher-nettle.c b/crypto/cipher-nettle.c
index 0267da5..879d831 100644
--- a/crypto/cipher-nettle.c
+++ b/crypto/cipher-nettle.c
@@ -227,7 +227,8 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
     case QCRYPTO_CIPHER_MODE_XTS:
         break;
     default:
-        error_setg(errp, "Unsupported cipher mode %d", mode);
+        error_setg(errp, "Unsupported cipher mode %s",
+                   QCryptoCipherMode_lookup[mode]);
         return NULL;
     }
 
@@ -357,7 +358,8 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         break;
 
     default:
-        error_setg(errp, "Unsupported cipher algorithm %d", alg);
+        error_setg(errp, "Unsupported cipher algorithm %s",
+                   QCryptoCipherAlgorithm_lookup[alg]);
         goto error;
     }
 
@@ -429,8 +431,8 @@ int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
         break;
 
     default:
-        error_setg(errp, "Unsupported cipher algorithm %d",
-                   cipher->alg);
+        error_setg(errp, "Unsupported cipher mode %s",
+                   QCryptoCipherMode_lookup[cipher->mode]);
         return -1;
     }
     return 0;
@@ -469,8 +471,8 @@ int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
         break;
 
     default:
-        error_setg(errp, "Unsupported cipher algorithm %d",
-                   cipher->alg);
+        error_setg(errp, "Unsupported cipher mode %s",
+                   QCryptoCipherMode_lookup[cipher->mode]);
         return -1;
     }
     return 0;
