Outlook shows html code instead of rendering the actual html itself

This sounds like the same problem reported in this Microsoft Q&A thread.

https://learn.microsoft.com/en-us/answers/questions/5520490/suddenly-most-of-my-e-mails-contain-unintelligble

Hi Chevron, 

I apologized for this inconvenience that is causing you I understand the actual message itself isn’t showing up but only the HTML code. Let me help you on this issue but I need to know if you are seeing any red x or any broken image icon in place of the picture? For initial troubleshooting please follow this procedure below 

To ensure Outlook displays emails correctly, start by checking message format settings. Go to File and select options then select Mail now select HTML for composing messages and uncheck Read all standard mail in plain text under Trust Center, Email Security. Next, enable image display by navigating to File and Options then Trust Center and Automatic Download and uncheck the options blocking images. If issues persist repair your Outlook profile via File then select Account Settings then click Repair, then restart Outlook. Verify language and region settings in Windows Settings then select Time & Language from the Language & Region be sure they align with Outlook’s language. For advanced troubleshooting reset the SecureTemp folder by clearing its contents see the attached screenshot for the folder path

 However with regards to the setting your outlook to POP3 start by opening the app and navigating to File  and  select Account Settings. Select New under the Email tab to add your account. Choose Manual setup and then pick POP. Fill in your details, including your name, email address, and server information like pop-mail.outlook.com for incoming and smtp-mail.outlook.com for outgoing. Don’t forget your username and password. Next, go to More Settings to configure authentication and encryption options ensuring your incoming server uses SSL port 995 and outgoing uses TLS (port 587). Now test the settings and if everything works you can click Finish to complete the setup 

If there’s anything more you’d like to share or questions, please don’t hesitate to reach out.  

Warm regards,  

Marcelo Mendoza 

Hi,

I have the exact same problem here, it seems like an error on Microsoft side.

NOT ALL messages distorted, but only SOME, mostly which has ANY connection with any MS services. Ie. if I send to myself an email from an outlook.com account it will be distorted. The rest arrives fine.

It seems like an MS misconfiguration which brakes the html code.

Hi @Ch3vr0n,

Thank you for reaching out and for providing this excellent, comprehensive list of troubleshooting steps. I can certainly understand how frustrating it is to be facing this kind of issue, especially after you've already done so much to try and fix it yourself.

First, could you tell me if you're seeing this issue only in the Outlook desktop application, or if the same thing happens when you check your emails on Outlook for the web? This will help me figure out the best way to tackle this for you.

Let's work through the most likely solutions, starting with the one that most often resolves these kinds of widespread issues.

1. Create a New Outlook Profile

Even though you reinstalled Windows and Outlook, your old Outlook profile data might still be present and corrupt. A new profile will force Outlook to rebuild its configuration from scratch, which is the most reliable way to fix a wide range of strange behavior.

Important: Do not delete your old profile until you confirm the new one is working. Your POP3 data files (.pst) will remain safe and separate.

1. Close Outlook completely.
2. Open the Control Panel. You can find this by searching for "Control Panel" in the Windows Start Menu.
3. In the Control Panel, change the view to "Small icons" and find Mail (Microsoft Outlook). This will open the Mail Setup dialog.
4. Click on Show Profiles...
5. Click Add... to create a new profile. Give it a simple name like "New Profile".
6. Follow the prompts to add your email accounts. You will need to re-add your POP3 accounts manually. Ensure you configure them as POP3 as before.
7. Once the accounts are set up in the new profile, select the option "Always use this profile" and choose your new profile from the dropdown list.
8. Click OK and open Outlook.

If the problem was due to a corrupted profile, this step should fix it, and your new incoming emails will render correctly.

2. Repair Your Office Installation

You mentioned reinstalling, but sometimes a targeted repair can fix underlying issues that a full reinstall misses.

1. Go to Windows Settings > Apps > Installed apps.
2. Find your Microsoft Office or Microsoft 365 installation in the list.
3. Click the three dots next to it and select Modify.
4. Choose Online Repair (which is more comprehensive than a Quick Repair) and follow the prompts.

3. Verify and Standardize Windows Language Settings

You've already looked into this in great detail, which is excellent. While a mix of languages usually works without issue, in rare cases, it can cause obscure bugs. For troubleshooting purposes, it may be worth temporarily setting all language and region settings to a single, consistent choice (e.g., all to English-United Kingdom) just to rule out any conflict.

PC Settings > Time & Language > Language & region.

Administrative language settings (in the same menu).

Please try these solutions in the order provided and let me know if any of them help resolve the issue. If the problem persists after trying all these methods, we can explore further troubleshooting steps.

Warm regards   

Chloe L. | Microsoft Q&A Support Specialist

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