How to resolve ' error TS2351: Cannot use 'new' with an expression whose type lacks a call or construct signature.'? : <p>I am importing a .js file (so not a .ts-file) called Auth.js into my reactjs&amp;typescript application, so in my component I have this:</p>

<pre><code>import * as Auth from '../Auth/Auth';
..
const auth = new Auth();
</code></pre>

<p>This is part of my Auth.js:</p>

<pre><code>    export default class Auth {
        auth0 = new auth0.WebAuth({
            domain: AUTH_CONFIG.domain,
            clientID: AUTH_CONFIG.clientId,
            redirectUri: AUTH_CONFIG.callbackUrl,
            audience: `https://${AUTH_CONFIG.domain}/userinfo`,
            responseType: 'token id_token',
            scope: 'openid'
        });

        constructor() {
            this.login = this.login.bind(this);
            this.logout = this.logout.bind(this);
            this.handleAuthentication = this.handleAuthentication.bind(this);
            this.isAuthenticated = this.isAuthenticated.bind(this);
        }
..
</code></pre>

<p>When I run webpack I get the following error message:</p>

<pre><code>ERROR in ./src/containers/main.tsx
(16,14): error TS2351: Cannot use 'new' with an expression whose type lacks a call or construct signature.
</code></pre>

<p>How can I resolve this TS-error?</p>
