1. 确保您为Lambda函数启用了正确的IAM权限，以便使用SMTP服务。在Lambda函数执行角色中添加以下权限：

"Effect": "Allow",
"Action": [
    "ses:SendEmail",
    "ses:SendRawEmail"
],
"Resource": "*"

2. 检查您的SMTP配置是否正确。AWS SES是一个SMTP服务器，因此您需要使用正确的SMTP配置信息来连接它。确保您的SMTP主机、端口、用户名和密码正确，并且SSL或TLS设置正确。

以下是一个使用Python的AWS Lambda连接到SES SMTP服务器发送邮件的示例代码：

import os
import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from email.mime.application import MIMEApplication

def send_email(event, context):
    try:
        # SMTP邮件参数
        smtp_host = 'email-smtp.us-west-2.amazonaws.com'
        smtp_port = 587
        smtp_username = '[your-smtp-username-here]'
        smtp_password = '[your-smtp-password-here]'

        # 邮件内容参数
        sender = '[your-sender-email-address-here]'
        recipient = '[your-recipient-email-address-here]'
        subject = 'Test Email from AWS Lambda'
        body_text = 'This email was sent from an AWS Lambda function.'

        # 创建邮件对象
        msg = MIMEMultipart()
        msg['Subject'] = subject
        msg['From'] = sender
        msg['To'] = recipient

        # 添加邮件正文
        body = MIMEText(body_text)
        msg.attach(body)

        # 添加附件
        attachment = MIMEApplication(open('test.pdf', 'rb').read())
        attachment.add_header('Content-Disposition', 'attachment', filename='test.pdf')
        msg.attach(attachment)

        # 创建SMTP客户端
        client = smtplib.SMTP(smtp_host, smtp_port)
        client.ehlo()
        client.starttls()
        client.login(smtp_username, smtp_password)

        # 发送邮件
        client.sendmail(sender, recipient, msg.as_string())
        client.close()