diff --git a/src/cnn/neuron_io.c b/src/cnn/neuron_io.c
index 465c77a..d961b2e 100644
--- a/src/cnn/neuron_io.c
+++ b/src/cnn/neuron_io.c
@@ -26,6 +26,10 @@ void write_network(char* filename, Network* network) {
     int indice_buffer = 0;
 
     ptr = fopen(filename, "wb");
+    if (!ptr) {
+        printf("Impossible d'ouvrir le fichier %s en écriture\n", filename);
+        exit(1);
+    }
 
     // Le buffer est composé de:
     // - MAGIC_NUMBER (1)
@@ -153,6 +157,10 @@ Network* read_network(char* filename) {
     Network* network = (Network*)nalloc(1, sizeof(Network));
 
     ptr = fopen(filename, "rb");
+    if (!ptr) {
+        printf("Impossible de lire le fichier %s\n", filename);
+        exit(1);
+    }
 
     uint32_t magic;
     uint32_t size;
diff --git a/src/common/mnist.c b/src/common/mnist.c
index 8e684fa..5ba874a 100644
--- a/src/common/mnist.c
+++ b/src/common/mnist.c
@@ -33,6 +33,10 @@ int* read_mnist_images_parameters(char* filename) {
     FILE *ptr;
     
     ptr = fopen(filename, "rb");
+    if (!ptr) {
+        printf("Impossible de lire le fichier %s\n", filename);
+        exit(1);
+    }
 
     uint32_t magic_number;
     uint32_t number_of_images;
@@ -64,6 +68,10 @@ uint32_t read_mnist_labels_nb_images(char* filename) {
     FILE *ptr;
     
     ptr = fopen(filename, "rb");
+    if (!ptr) {
+        printf("Impossible de lire le fichier %s\n", filename);
+        exit(1);
+    }
 
     uint32_t magic_number;
     uint32_t number_of_images;
@@ -87,6 +95,10 @@ int*** read_mnist_images(char* filename) {
     FILE *ptr;
     
     ptr = fopen(filename, "rb");
+    if (!ptr) {
+        printf("Impossible de lire le fichier %s\n", filename);
+        exit(1);
+    }
 
     uint32_t magic_number;
     uint32_t number_of_images;
@@ -123,6 +135,10 @@ unsigned int* read_mnist_labels(char* filename) {
     FILE* ptr;
 
     ptr = fopen(filename, "rb");
+    if (!ptr) {
+        printf("Impossible de lire le fichier %s\n", filename);
+        exit(1);
+    }
 
     uint32_t magic_number;
     uint32_t number_of_items;
diff --git a/src/dense/neuron_io.c b/src/dense/neuron_io.c
index 1074adf..f755dcc 100644
--- a/src/dense/neuron_io.c
+++ b/src/dense/neuron_io.c
@@ -55,6 +55,10 @@ Network* read_network(char* filename) {
     Network* network = (Network*)malloc(sizeof(Network));
 
     ptr = fopen(filename, "rb");
+    if (!ptr) {
+        printf("Impossible de lire le fichier %s\n", filename);
+        exit(1);
+    }
 
     uint32_t magic_number;
     uint32_t nb_layers;
@@ -110,6 +114,10 @@ void write_network(char* filename, Network* network) {
     int nb_neurons[nb_layers+1];
 
     ptr = fopen(filename, "wb");
+    if (!ptr) {
+        printf("Impossible d'ouvrir le fichier %s en écriture\n", filename);
+        exit(1);
+    }
 
     uint32_t buffer[nb_layers+2];
 
@@ -174,6 +182,10 @@ Network* read_delta_network(char* filename) {
     Network* network = (Network*)malloc(sizeof(Network));
 
     ptr = fopen(filename, "rb");
+    if (!ptr) {
+        printf("Impossible de lire le fichier %s\n", filename);
+        exit(1);
+    }
 
     uint32_t magic_number;
     uint32_t nb_layers;
@@ -229,6 +241,10 @@ void write_delta_network(char* filename, Network* network) {
     int nb_neurons[nb_layers+1];
 
     ptr = fopen(filename, "wb");
+    if (!ptr) {
+        printf("Impossible d'ouvrir le fichier %s en écriture\n", filename);
+        exit(1);
+    }
 
     uint32_t buffer[nb_layers+2];