Backed Up Mail - Unconverted Mail Guide
※ Last updated: 2025-09-08
SHIELD Mail'sUnconverted MailThe menu is a screen where you can check and manage emails that could not be converted normally due to an error during mail security conversion. The emails are stored for a maximum of 2 months and will be automatically deleted thereafter.
1. What is an unconverted email?
**What is an unconverted email?**An error occurred during email security conversion, meaning that the email was not converted properly.
- If SHIELD Mail fails to convert the original email into a secure email
- Main causes of failure: attachment issues, authentication/authorization errors, etc.
2. Menu Entry
Backed Up Mail > Unconverted MailYou can access the unconverted mail management screen from the menu.

- You can select a period (7 days, 30 days, 45 days, 60 days) and a custom period at the top of the screen.
SIDYou can search for specific emails by entering keywords for the sender/receiver.
3. Screen Composition
3-1. List Table Items
| column | Description |
|---|---|
| date | Date and time the email was received |
| Unconverted attachment | Number of attachment files that failed to convert |
| Type | Error Type |
| Sender | Sender's email address |
| recipient | Recipient's email address |
| Title | Email Subject |
| SID | Unique identifier assigned by the system (Session ID) |
3-2. Detailed View
When you click an item in the list, detailed information is displayed in the right panel.

-
Unconverted Information Tab
- date
- Conversion Error Types
- file name
- Error Codes and Detailed Messages
- Related Policy Name
-
Details Tab
- Sender / Receiver
- SID
- Title
- Conversion results by attachment file (success/failure indication)
3-3. Unconverted Error Types
The types of errors that can be confirmed in unconverted emails are as follows:
① Policy-related errors
- Policy request failed
- Policy Evaluation Failure
- Policy not found
② File conversion related errors
- File conversion failed
- File decryption failed
- File encryption failed
③ File System Related Errors
- File not found
- File Read Error
- File write error
- No file access permission
- The file already exists.
④ Authentication/Authorization Related Errors
- Authentication failed
- Permission Denied
- Invalid SHIELD ID
- Token Expiration
⑤ API call related errors
- API call failed
- Container Service Error
- ZTCA connection error
- Key storage error
- Label API Error
⑥ System-related errors
- System Error
- Invalid parameter
- Incorrect system status
- Timeout
⑦ Others
- Unknown error
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