In order to autopost your article to Twitter, Twitter requires you to set up an application with them. This documentation provides instructions on how to properly set this up.
Step 1 - Creating New App
Open up Twitter Application Management site at https://apps.twitter.com/. Login to the site using your Twitter account.
Once you have logged in, click on the Create New App button.
Step 2 - Setting Up The Application
Enter the required details for the application, read and agree to the terms. Once ready, click on Create your Twitter application button.
After the app is created, you will be redirected to your application and you will see the following page.
Step 3 - Furnishing the Twitter App
Additional permission is required by the app. Navigate to the Settings tab and you will see a checkbox that asks: Allow this application to be used to Sign in with Twitter. You have to make sure this checkbox is ticked for Twitter app to work properly.
Step 4 - Keys & Access Tokens
On this page you will find the Consumer Key (API Key) and Consumer Secret (API Secret). You will need to copy and paste both of these keys into Twitter Autoposting section in EasyArticles.
Step 5 - Permissions
Check and make sure that the app has read and write permission. If not, select the Read and Write access option and click on the Update Settings button to save your changes.
Step 6 - Autoposting Integration
Once you have done all that, the app is now complete. Add the Consumer Key (API Key) and Consumer Secret (API Secret) which you have obtained from step 4 into EasyArticle's Twitter Autoposting settings. Twitter's autoposting settings can be found by navigating to Components > EasyArticles > Autoposting > Twitter.
Once you have done adding them, click on the Save button to store the keys.
Step 7 - Autoposting Authentication
After you have added the Consumer Key (API Key) and Consumer Secret (API Secret) as outlined in Step 6, it's time to authenticate them. Click on Sign in with Twitter button. A dialog popup will appear for the authentication process. Click on Authorize app button to authenticate it.