How to Fix Microsoft Outlook Error 0x80040115

Unable to send emails and wondering how to fix the Microsoft Outlook error 0x80040115 on your PC?


Fix: Microsoft Outlook Error 0x80040115


With thousands of messaging apps with cool features, sending emails might seem a little old school, but it is not. Ask its importance from a fresh graduate who is impatiently waiting for that one acceptance letter and checks the email app God knows how many times every day! 

As much as modern communication software has tried to kill email, over 4 billion people still use it daily. One such email software program is Outlook, which is available as a part of the Microsoft Office suite. 

Microsoft Outlook offers the users to perform a wide range of tasks such as sending and receiving emails, managing calendars, storing contact names, and tracking tasks. However, like any other app, Microsoft Outlook sometimes fails to respond. 

A common issue that prevents the users from sending emails via Microsoft Outlook is the error 0x80040115. If you are facing the 0x80040115 error, you are in the right place. 

This guide will walk you through the process of fixing the 0x80040115 error in a few simple steps. 

Let’s get straight into it. 


1. Clear DNS Cache. 

Domain Name System (DNS) is the phonebook of the internet. DNS works by translating the domain names to IP addresses. In simple words, think of DNS as an address book in your phone that matches people’s names with their email addresses and contact numbers. 

When you open a webpage on your browser, the browser stores temporary information about your lookup for future use. Similarly, when you open an app on your PC, the operating system stores temporary information about the app to help retrieve data faster in the future. These temporary data files are also known as DNS cached files. 

There are times when caches files can get corrupted. As a result, you fail to open certain apps or web pages on your browser. If you face the Microsoft Outlook error 0x80040115, there is a chance that corrupt cached files are causing the issue. In this scenario, you can solve the error by deleting DNS cached files on your PC. 

Here is what you need to do:

  1. Type cmd in the search bar and click on Run as administrator to launch Command Prompt with administrative rights on your PC. 
  2. In the elevated Command Prompt window, type the command mentioned below and hit Enter to execute it. 
ipconfig /flushdns

Fix: Microsoft Outlook Error 0x80040115


  1. Once the command is executed, open Microsoft Outlook and see if the error is resolved. 

If a corrupt DNS cached file was causing the issue, clearing the cache would solve the error. You should now be able to send emails via Microsoft Outlook without any problems. 



2. Change Profile Settings.

Some features like managing contacts and sending emails in Outlook require an ‘Exchange Server’ account. One possible cause of the Microsoft Outlook error 0x80040115 is that you are using Outlook with disabled ‘Encrypt data between Microsoft Office Outlook and Microsoft Exchange’ profile setting. If this profile setting is disabled, your account will not be able to send emails. 

A simple solution to this issue is to enable the ‘Encrypt data between Microsoft Office Outlook and Microsoft Exchange’ profile setting. 

Here is how you can do it:

  1. Go to the Control Panel and type Mail in the search box. 
  2. Click on Mail and select Show Profiles
  3. Now select your profile and click on Properties
  4. Click on Email Accounts.

Mail Setup Profile Control Panel


  1. Highlight your account and select Change
  2. Next, locate More Settings at the bottom of the window and click on it. 
  3. Finally, click on the Security tab and checkmark the Encrypt data between Microsoft Office Outlook and Microsoft Exchange option. 

Fix: Microsoft Outlook Error 0x80040115


  1. Click OK to save the changes. 

That’s it. Hopefully, changing the profile settings will solve the error on your PC. However, if the ‘Encrypt data between Microsoft Office Outlook and Microsoft Exchange’ option was already check-marked, this means that there is another reason preventing you from sending emails. In this case, proceed to the next method below. 



3. Launch Outlook in Safe Mode. 

In some cases, third-party add-ins cause the Microsoft Outlook error 0x80040115, and it can be fixed by launching Outlook in Safe Mode. Safe Mode is a diagnostic mode intended to fix most, if not all, issues within an application and even an operating system.

Here is how you can fix the Microsoft Outlook error 0x80040115 by launching Outlook in Safe Mode:

  1. Press Windows + R keys simultaneously to open a Run dialogue box. 
  2. Type ‘Outlook /safe’ in the text box and hit Enter
  3. Once Outlook launches in Safe Mode, try sending an email to see if the error is resolved. 
  4. If the error is fixed, go to File and click on Options
  5. Locate Add-ins on the left panel and click on it. 

Check for Add-ins in Control Panel


  1. Finally, remove all the add-ins. 

That’s it. If the add-ins were causing the issue, removing them in the Safe Mode will fix the error. However, if you failed to send an email while using Outlook in the Safe Mode, see the next method below. 



4. Disable Antivirus. 

If you use Windows Defender or a third-party antivirus program on your PC, try disabling it temporarily to see if doing so resolved the issue. There are times when anti-virus software prevents particular apps from functioning because it ‘assumes’ that the app can cause errors in your PC.

 While most of the time, these assumptions are correct, sometimes the anti-virus software is just overzealous to block files. As a result, you face errors while trying to execute operations. 

You can solve this issue by temporarily disabling the antivirus and checking if doing so helped. If disabling the anti-virus resolved the issue, you can then add Outlook to the exclusion list. 



5. Repair Outlook Installation. 

If none of the methods mentioned above works for you, we recommend repairing Outlook installation. 

Microsoft Office applications break at one point or another. Luckily, Microsoft Office comes with a ‘Repair tool’ that is based on Click-to-Run technology. This allows the users to repair the faulty Office applications without downloading installation media. 

Here is how you can repair Outlook installation on your PC:

  1. Press Windows + X keys simultaneously and select Apps and Features from the list displayed on your screen. 
  2. In the list of applications, locate Microsoft Outlook and click on it. If you are using Microsoft Office, search for it, and perform the steps mentioned below. 
  3. Select Modify
  4. Now, run a Quick Repair. Wait for the process to complete and check if Quick Repair resolved the error. 

Fix: Microsoft Outlook Error 0x80040115


  1. If the error persists, perform an Online Repair

Hopefully, performing an Online Repair will solve the error on your PC once and for all. 

This brings us to the end of our guide on fixing the Microsoft Outlook error 0x80040115. We tried to walk you through the troubleshooting steps in detail and hope that the steps listed above helped you solve the issue. If you have any questions regarding the steps, please let us know in the comment section below. We will try our best to help you out. 


If this guide helped you, please share it. 🙂


  • Zainab Falak

    Zainab Falak is a staff writer for Saint and an expert in Microsoft Windows, having authored more than 200 posts. She has a Bachelors in Actuarial Sciences and her passion for computers extends to exploring various aspects, from UI customization to the Windows registry and exploring error codes. Twitter LinkedIn

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