diff --git a/package.json b/package.json
index 78f0174e7..ee9e0cd67 100644
--- a/package.json
+++ b/package.json
@@ -63,6 +63,7 @@
     "@types/minimatch": "3.0.3",
     "@types/node": "12.6.2",
     "@types/request": "2.48.2",
+    "@types/semver": "6.0.1",
     "@typescript-eslint/eslint-plugin": "1.12.0",
     "@verdaccio/babel-preset": "0.2.1",
     "@verdaccio/eslint-config": "0.0.1",
diff --git a/src/lib/local-storage.ts b/src/lib/local-storage.ts
index 00244691c..9e81542da 100644
--- a/src/lib/local-storage.ts
+++ b/src/lib/local-storage.ts
@@ -3,7 +3,7 @@ import UrlNode from 'url';
 import _ from 'lodash';
 import { ErrorCode, isObject, getLatestVersion, tagVersion, validateName } from './utils';
 import { generatePackageTemplate, normalizePackage, generateRevision, getLatestReadme, cleanUpReadme, normalizeContributors } from './storage-utils';
-import { API_ERROR, DIST_TAGS, STORAGE, USERS } from './constants';
+import { API_ERROR, DIST_TAGS, HTTP_STATUS, STORAGE, USERS } from './constants';
 import { createTarballHash } from './crypto-utils';
 import { prepareSearchPackage } from './storage-utils';
 import loadPlugin from '../lib/plugin-loader';
@@ -34,10 +34,10 @@ class LocalStorage implements IStorage {
       return callback(ErrorCode.getNotFound('this package cannot be added'));
     }
 
-    storage.createPackage(name, generatePackageTemplate(name), (err: VerdaccioError): void => {
+    storage.createPackage(name, generatePackageTemplate(name), err => {
       // FIXME: it will be fixed here https://github.com/verdaccio/verdaccio/pull/1360
       // @ts-ignore
-      if (_.isNull(err) === false && err.code === STORAGE.FILE_EXIST_ERROR) {
+      if (_.isNull(err) === false && (err.code === STORAGE.FILE_EXIST_ERROR || err.code === HTTP_STATUS.CONFLICT)) {
         return callback(ErrorCode.getConflict());
       }
 
@@ -65,7 +65,7 @@ class LocalStorage implements IStorage {
 
     storage.readPackage(name, (err, data: Package): void => {
       if (_.isNil(err) === false) {
-        if (err.code === STORAGE.NO_SUCH_FILE_ERROR) {
+        if (err.code === STORAGE.NO_SUCH_FILE_ERROR || err.code === HTTP_STATUS.NOT_FOUND) {
           return callback(ErrorCode.getNotFound());
         } else {
           return callback(err);
@@ -419,13 +419,13 @@ class LocalStorage implements IStorage {
 
     const writeStream: IUploadTarball = storage.writeTarball(filename);
 
-    writeStream.on('error', (err: VerdaccioError): void => {
+    writeStream.on('error', err => {
       // @ts-ignore
-      if (err.code === STORAGE.FILE_EXIST_ERROR) {
+      if (err.code === STORAGE.FILE_EXIST_ERROR || err.code === HTTP_STATUS.CONFLICT) {
         uploadStream.emit('error', ErrorCode.getConflict());
         uploadStream.abort();
-        // @ts-ignore
-      } else if (err.code === STORAGE.NO_SUCH_FILE_ERROR) {
+      // @ts-ignore
+      } else if (err.code === STORAGE.NO_SUCH_FILE_ERROR || err.code === HTTP_STATUS.NOT_FOUND) {
         // check if package exists to throw an appropriate message
         this.getPackageMetadata(name, function(_err: VerdaccioError, _res: Package): void {
           if (_err) {
@@ -531,9 +531,9 @@ class LocalStorage implements IStorage {
       }
     };
 
-    readTarballStream.on('error', function(err: VerdaccioError): void {
+    readTarballStream.on('error', function(err) {
       // @ts-ignore
-      if (err && err.code === STORAGE.NO_SUCH_FILE_ERROR) {
+      if (err.code === STORAGE.NO_SUCH_FILE_ERROR || err.code === HTTP_STATUS.NOT_FOUND) {
         stream.emit('error', e404('no such file available'));
       } else {
         stream.emit('error', err);
@@ -624,7 +624,7 @@ class LocalStorage implements IStorage {
   private _readPackage(name: string, storage: any, callback: Callback): void {
     storage.readPackage(name, (err, result): void => {
       if (err) {
-        if (err.code === STORAGE.NO_SUCH_FILE_ERROR) {
+        if (err.code === STORAGE.NO_SUCH_FILE_ERROR || err.code === HTTP_STATUS.NOT_FOUND) {
           return callback(ErrorCode.getNotFound());
         } else {
           return callback(this._internalError(err, STORAGE.PACKAGE_FILE_NAME, 'error reading'));
@@ -666,7 +666,7 @@ class LocalStorage implements IStorage {
     storage.readPackage(pkgName, (err, data): void => {
       // TODO: race condition
       if (_.isNil(err) === false) {
-        if (err.code === STORAGE.NO_SUCH_FILE_ERROR) {
+        if (err.code === STORAGE.NO_SUCH_FILE_ERROR || err.code === HTTP_STATUS.NOT_FOUND) {
           data = generatePackageTemplate(pkgName);
         } else {
           return callback(this._internalError(err, STORAGE.PACKAGE_FILE_NAME, 'error reading'));
diff --git a/src/lib/utils.ts b/src/lib/utils.ts
index e19f41cd9..1bc0ff545 100644
--- a/src/lib/utils.ts
+++ b/src/lib/utils.ts
@@ -263,16 +263,20 @@ export function parseAddress(urlAddress: any): any {
  * @return {Array} sorted Array
  */
 export function semverSort(listVersions: string[]): string[] {
-  return listVersions
-    .filter(function(x): boolean {
-      if (!semver.parse(x, true)) {
-        Logger.logger.warn({ ver: x }, 'ignoring bad version @{ver}');
-        return false;
-      }
-      return true;
-    })
-    .sort(semver.compareLoose)
-    .map(String);
+  return (
+    listVersions
+      .filter(function(x): boolean {
+        if (!semver.parse(x, true)) {
+          Logger.logger.warn({ ver: x }, 'ignoring bad version @{ver}');
+          return false;
+        }
+        return true;
+      })
+      // FIXME: it seems the @types/semver do not handle a legitimate method named 'compareLoose'
+      // @ts-ignore
+      .sort(semver.compareLoose)
+      .map(String)
+  );
 }
 
 /**
diff --git a/yarn.lock b/yarn.lock
index f1478dc6c..49b27947e 100644
Binary files a/yarn.lock and b/yarn.lock differ