Your emails are sending without formatting, images, or links. This happens because Outlook is configured to use plain text as the default message format. The setting can be changed in your account options or by a specific mail format rule.
This article explains why Outlook defaults to plain text and provides the steps to restore HTML formatting. You will learn how to change the default setting for new messages and replies.
Key Takeaways: Restoring HTML Format in Outlook
- File > Options > Mail > Compose messages in this format: Sets the default format for all new emails you write.
- File > Options > Mail > Replies and forwards: Controls the format used when you reply to or forward a received message.
- Format Text tab > HTML button: Manually switches a single open message from plain text to HTML format before sending.
Why Outlook Switches to Plain Text Format
Outlook can send messages in three formats: HTML, Rich Text, and Plain Text. HTML is the standard, allowing for fonts, colors, and embedded images. Plain Text strips all styling and is useful for compatibility with very old email systems.
The program may default to Plain Text due to a changed global setting. This often occurs after updating Office or if an administrator configures a group policy. Another cause is replying to a message originally sent in plain text, as Outlook can be set to match the format of the original email.
Some add-ins or security software can also force plain text to prevent potential scripting threats. Checking your default message format is the first step to diagnose this issue.
Steps to Set HTML as the Default Format
Follow these steps to configure Outlook to use HTML format for all new messages and replies. This is a permanent change in the application options.
- Open Outlook Options
Click the File tab in the top-left corner of the Outlook window. Select Options from the left-hand menu to open the Outlook Options dialog box. - Navigate to Mail Settings
In the Outlook Options window, click the Mail category in the left sidebar. Scroll down to the “Compose messages” section. - Set the Compose Format
Find the dropdown menu labeled “Compose messages in this format.” Click it and select HTML from the list of options. This sets HTML as the default for all new emails. - Set the Reply Format
Just below, locate the dropdown for “Replying and forwarding.” Set this to “Reply in the format of the original message” or select HTML directly. The first option is recommended for consistency. - Apply the Changes
Click the OK button at the bottom of the Outlook Options window to save your new settings and close the dialog. The change takes effect immediately.
Changing the Format for a Single Message
If you need to fix one email already written in plain text, use the ribbon. With the message window open, go to the Format Text tab. In the Format group, click the HTML button. This converts the current message to HTML format, allowing you to add formatting before sending.
If Outlook Still Sends Plain Text After the Fix
Check the Account-Specific Setting
Some account types have a separate format setting. Go to File > Account Settings > Account Settings. Double-click your email account. Under the “More Settings” area, check the Internet Format or similar tab to ensure HTML is selected for outgoing mail.
Disable “Read as Plain Text” for Received Mail
A related setting can affect replies. Go to File > Options > Trust Center > Trust Center Settings. Select Email Security. Under “Read as Plain Text,” ensure the box for “Read all standard mail in plain text” is NOT checked. If it is, uncheck it and click OK twice.
Investigate Conflicting Add-ins
Add-ins can override default formats. Start Outlook in safe mode by holding Ctrl while clicking the Outlook icon. If emails send as HTML in safe mode, an add-in is causing the problem. Disable add-ins one by one from File > Options > Add-ins to find the culprit.
Outlook Message Format Comparison
| Item | HTML Format | Plain Text Format |
|---|---|---|
| Description | Standard web-like format with styling | Text only, no styling or images |
| Fonts & Colors | Fully supported | Not supported |
| Images | Can be embedded inline | Attached as separate files only |
| Hyperlinks | Clickable links | Display as full URL text |
| Compatibility | Excellent with modern clients | Universal, works with all systems |
| File Size | Larger due to formatting code | Very small |
You can now ensure all your emails are sent with full HTML formatting. Check the Format Text tab on individual messages if you need a quick override. For persistent issues, review your account-specific settings in the Account Settings menu. A useful advanced tip is to create a Quick Step that automatically changes a selected message’s format, saving time when correcting multiple drafts.