> Source: [sk182600](https://support.checkpoint.com/results/sk/sk182600)

# sk182600 - Error Message: "Must issue a STARTTLS command first (in reply to MAIL FROM command)"

| Property | Value |
|----------|-------|
| Solution ID | sk182600 |
| Date Created | 2024-08-19 |
| Last Modified | 2024-08-20 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R81.20, R81.10 (EOS) |
| OS | Gaia |
| Platform | 3000 |

## Symptoms

- * **Error Message:** Must issue a STARTTLS command first (in reply to MAIL FROM command)

  **Location:** `/var/log/maillog`

  This error indicates that the STARTTLS command must be issued before sending the MAIL FROM command, as recorded in the `/var/log/maillog` file.
* Emails status shows "deferred" or "bounced"

## Cause

**Issue with SMTP TLS Configuration After Gateway Upgrade**

Following a Security Gateway upgrade, the `smtp_use_tls` parameter for the next hop is set to `false` by default.

As a result, the next hop expects SMTP packets to be encrypted using TLS but does not receive them.

## Solution

This solution requires authentication. Please log in to view the full solution.

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