diff --git a/src/clients/HookClient.js b/src/clients/HookClient.js
index 4a80138..5a593cd 100644
--- a/src/clients/HookClient.js
+++ b/src/clients/HookClient.js
@@ -70,7 +70,12 @@ class HookClient {
       ).then(response => {
         resolve(response.body);
       }).catch(errResponse => {
-        reject(errResponse.message);
+        if (errResponse.statusCode === 404) {
+          reject('This is not the hook you are looking for.');
+        }
+        else {
+          reject(errResponse.message);
+        }
       });
     });
   }
@@ -108,8 +113,15 @@ class HookClient {
         }
       ).then(response => {
         resolve(response.body);
-      }).catch(err => {
-        reject(err.message);
+      }).catch(errResponse => {
+        if (errResponse.statusCode === 404) {
+          reject('The hook you want to update does not exist.');
+        }
+        else if (errResponse.statusCode === 409){
+          reject('A hook with this name already exists.');
+        } else {
+          reject(errResponse.message);
+        }
       });
     });
   }
diff --git a/tests/clients/HookClient.spec.js b/tests/clients/HookClient.spec.js
index df117b6..abeacb9 100644
--- a/tests/clients/HookClient.spec.js
+++ b/tests/clients/HookClient.spec.js
@@ -129,6 +129,33 @@ describe('hookClient', () => {
       });
     });
    
+    it('should return an error when request fails with 404', done => {
+      // Given
+      const error = { statusCode: 404, message: 'Error !' };
+      hookClient.httpClient.sendEndpointRequest = sinon.stub().returns(Promise.reject(error));
+
+      // When / Then
+      hookClient.getHook(token, hookName).then(result => {
+        done('should have failed');
+      }).catch(err => {
+        expect(err).to.be.equals('This is not the hook you are looking for.');
+        expect(hookClient.httpClient.sendEndpointRequest).to.have.been.calledOnce;
+        expect(hookClient.httpClient.sendEndpointRequest).to.have.been.calledWithExactly(
+          {
+            method: 'GET',
+            path: '/api/dispatcher/hooks/:hook'
+          },
+          {
+            headers: { 'x-auth-token': token },
+            pathVariables: {
+              hook: hookName
+            }
+          }
+        );
+        done();
+      });
+    });
+
     it('should return specified hook when request succeeds', done => {
       // Given
       const response = { body: hook };
@@ -218,6 +245,56 @@ describe('hookClient', () => {
       });
     });
 
+    it('should return an error message when request fails with 404', done => {
+      // Given
+      const error = { statusCode: 404, message: 'Error !' };
+      hookClient.httpClient.sendEndpointRequest = sinon.stub().returns(Promise.reject(error));
+
+      // When / Then
+      hookClient.updateHook(token, hookName, newHook).then(result => {
+        done('should have failed');
+      }).catch(err => {
+        expect(err).to.be.equals('The hook you want to update does not exist.');
+        expect(hookClient.httpClient.sendEndpointRequest).to.have.been.calledOnce;
+        expect(hookClient.httpClient.sendEndpointRequest).to.have.been.calledWithExactly(
+          {
+            method: 'PUT',
+            path: '/api/dispatcher/hooks/:hook'
+          }, {
+            headers: { 'x-auth-token': token },
+            pathVariables: { hook : hookName},
+            body: newHook
+          }
+        );
+        done();
+      });
+    });
+
+    it('should return an error message when request fails with 409', done => {
+      // Given
+      const error = { statusCode: 409, message: 'Error !' };
+      hookClient.httpClient.sendEndpointRequest = sinon.stub().returns(Promise.reject(error));
+
+      // When / Then
+      hookClient.updateHook(token, hookName, newHook).then(result => {
+        done('should have failed');
+      }).catch(err => {
+        expect(err).to.be.equals('A hook with this name already exists.');
+        expect(hookClient.httpClient.sendEndpointRequest).to.have.been.calledOnce;
+        expect(hookClient.httpClient.sendEndpointRequest).to.have.been.calledWithExactly(
+          {
+            method: 'PUT',
+            path: '/api/dispatcher/hooks/:hook'
+          }, {
+            headers: { 'x-auth-token': token },
+            pathVariables: { hook : hookName},
+            body: newHook
+          }
+        );
+        done();
+      });
+    });
+
     it('should return the updated hook', done => {
       // Given
       const response = { body: newHook };