Connect CRM-NG SMTP to MailerSend with an API token and a verified domain, and understand the trial account limits.

This guide shows you how to send your WordPress email through MailerSend, a modern transactional email service. It suits sites that want a clean dashboard and a generous free allowance to start. MailerSend's free plan includes a monthly quota; check its site for the current figure.

The MailerSend mailer sends through MailerSend's API with an API token. MailerSend only sends from domains you have verified, and new accounts start with trial limits.

Before you start

• A MailerSend account (sign up at https://www.mailersend.com/).
• A domain you control, with access to its DNS records.
• Administrator access to your WordPress site.

Step 1: Add and verify your domain

1. Sign in to MailerSend

   Go to https://app.mailersend.com/ and sign in.

2. Open Domains

   Open Domains from the side menu and choose Add domain.

3. Enter your domain

   Type the domain you send from, for example yourdomain.com.

4. Publish the records

   MailerSend lists records for SPF (TXT), DKIM and a return path (CNAME). Add them at your DNS provider exactly as shown.

5. Verify

   Return to MailerSend and press Verify until the domain shows as verified.

See Adding DNS records for help with DNS.

Step 2: Create an API token

1. Open API tokens

   Open the API tokens page (look under Integrations → API tokens, or use the plugin's Get API Key link, which goes to https://app.mailersend.com/api-tokens).

2. Generate a token

   Choose Generate new token, name it after your site, and pick the domain it may send for.

3. Set the access

   Give it full access to email sending, or choose custom access and allow at least email sending.

4. Copy the token

   Copy it now. MailerSend shows it once.

Step 3: Connect in CRM-NG SMTP

1. Choose the mailer

   In WordPress, open CRM-NG SMTP → Settings → General and set Mailer to MailerSend.

2. Paste the token

   Paste the token into API Key.

3. Set the plan option

   Turn on Professional Plan only if your MailerSend plan allows custom email headers. While it is off, CRM-NG SMTP leaves custom headers out of each message, which is what lower plans need. Turning it on with a plan that lacks the feature can make MailerSend refuse messages.

4. Set the sender

   Set From Email to an address on your verified domain and set From Name. Tick Force From Email so other plugins cannot use an unverified domain.

5. Save

   Press Save Settings.

Send a test email

Open CRM-NG SMTP → Tools → Email Test, enter your address in Send To, and press Send Email. While on a trial, send to the administrator address of your MailerSend account. MailerSend's Activity page shows the result. See Sending a test email.

Troubleshooting

• The account is still on trial and the recipient is someone else: Trial accounts can only send to the admin address
• The From domain is not verified: Domain not verified
• The token is wrong, deleted, or not allowed for this domain: Unauthenticated
• Your monthly quota is used up: Email sending limit reached
• The recipient bounced before and is blocked: Email address in suppression list
• Mail arrives in spam: Emails landing in spam

Related

• Choosing a mail service
• Adding DNS records: SPF, DKIM and DMARC
• Verifying your DNS records
• Sender name, address and the Force settings
• Debug events