# alimail-compatibility

Part of **ALIMAIL**

# Alibaba Mail Email Delivery Console Guide

## Operations Overview

| Operation | Console Entry Path | Prerequisites | Description |
|----------|-------------------|---------------|-------------|
| Prevent Winmail.dat Files | File > Options > Mail > Compose messages area | Access to Outlook client (version 2013 or later), Administrative privileges for registry edits | Configure Outlook to avoid sending proprietary TNEF/Winmail.dat attachments that disrupt email compatibility |

## Operation Steps

### Prevent Winmail.dat Files

**Navigation**: File > Options > Mail > Compose messages area

**Prerequisites**:
- Access to Outlook client (version 2013 or later)
- Administrative privileges for registry edits (for advanced method)

1. Open Outlook and go to **File** (menu) — located in the top-left corner  
   - Notes: This opens the Backstage view.

2. Click **Options** (link) — appears in the left sidebar of the Backstage view  
   - Notes: The Outlook Options dialog opens.

3. In the left panel of the Options dialog, select **Mail** (tab)  
   - Notes: This displays mail-related settings.

4. In the **Compose messages** area, locate the dropdown labeled **Compose messages in this format** (dropdown)  
   - Element: **Compose messages in this format** (dropdown) — within the "Compose messages" section  
   - Action: Select either **HTML** or **Plain Text** from the dropdown options

5. Click the **Internet Format** (link) — located just below the format dropdown in the same section  
   - Notes: A new dialog titled "Internet Message Formats" appears.

6. In the dialog, choose either **Convert to HTML format** or **Convert to Plain Text format** (radio)  
   - Element: **Convert to HTML format** / **Convert to Plain Text format** (radio) — under "When sending messages in Rich Text format to Internet recipients"  
   - Notes: This ensures Rich Text emails are converted to a universally compatible format before sending.

7. (Optional – Advanced) Edit the Windows Registry to permanently disable TNEF:  
   - Open the Windows Registry Editor (requires administrative rights)  
   - Navigate to: `HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Preferences`  
   - Create a new **DWORD (32-bit) Value** named **DisableTNEF** (text_input)  
     - Element: **DisableTNEF** (text_input) — in the right pane of the Preferences key  
     - Value: Set to `1` to disable TNEF encoding entirely  
   - Notes: Modifying the registry incorrectly can affect system stability. Back up the registry before proceeding.

**Form Fields**: None

## FAQ

Q: Why do some recipients receive a Winmail.dat file instead of my formatted email?
A: Outlook uses TNEF (Transport Neutral Encapsulation Format) when sending in Rich Text format to other Exchange/Outlook users. Non-Outlook clients cannot interpret TNEF, so they see only the Winmail.dat attachment. Switching to HTML or Plain Text prevents this.

Q: Do I need to change settings for every email I send?
A: No. Configuring the default message format and Internet Format options in Outlook applies globally to all future messages sent to Internet recipients.

Q: Can I apply this setting across an entire organization?
A: Yes, via Group Policy or by deploying the DisableTNEF registry key through enterprise management tools. The UI method must be configured per user unless scripted.

Q: Will changing to Plain Text remove my email signature or images?
A: Yes. Plain Text strips all formatting, including fonts, colors, embedded images, and HTML signatures. Use HTML format if you need to preserve basic styling while avoiding Winmail.dat.

Q: Does this affect emails sent within my company (to other Outlook users)?
A: No. TNEF is only used internally between Exchange/Outlook systems. The Internet Format setting specifically controls how messages are sent to external (non-Exchange) recipients.

## Pricing & Billing

### Billing Model
Free

### Free Tier
No cost associated with using Outlook or these settings.

### Billing Notes
These settings are part of standard Outlook functionality and do not incur additional costs.