SMTP email setup

Connect SMTP to send Fileflare’s download emails from your own domain instead of Fileflare’s default noreply@digital-downloads.com. Customers see your store’s name in their inbox, deliverability improves with proper domain authentication, and you can use any SMTP-compatible service — Postmark, Brevo, Resend, MailerSend, Mailtrap, SendGrid, or your own mail server.

One thing to know before you start: the verification link Fileflare emails you expires 30 minutes after it’s sent, and it works once. Set the connection up when you have a few minutes to finish it, rather than saving now and clicking the link tomorrow.

When you’d use this

• You want emails to come from files@yourstore.com instead of Fileflare’s default address.
• You’re noticing emails landing in spam from the default sender — your own authenticated domain typically improves placement.
• You want analytics from your SMTP provider (open rates, click tracking) on top of Fileflare’s email tracking.
• You want full control of your email sending infrastructure (volume, IP, reputation).

Pick a provider

All these providers work with Fileflare. The decision usually comes down to deliverability, free-tier limits, and how technical you want to get. Quick guidance:

• Postmark — best overall. Excellent deliverability, simple setup, 100 emails/day free, paid from $15/mo. Recommended.
• Resend — modern, developer-friendly. Generous free tier, easy domain verification.
• Brevo (formerly Sendinblue) — easy to set up, 300 emails/day free. Note: Brevo’s link tracking can break Fileflare’s signed URLs — disable it in Brevo’s settings.
• MailerSend — solid free tier, clean dashboard.
• Mailtrap — good for testing; production use also works.
• SendGrid — works fine but no longer has a free tier; SMTP API has a 5,000-email lifetime cap per key.
• Your own mail server (Outlook, Yahoo, custom) — possible but more limited (Google Workspace SMTP is no longer available to new users; daily limits are tight on most personal accounts).

General SMTP setup

The exact button labels differ by provider, but the flow is the same:

1. Sign up for the SMTP provider.
2. Verify your domain so the provider can send mail on its behalf. Usually involves adding a few DNS records.
3. Generate an SMTP credential (username + password, or an API key used as both).
4. In Fileflare, go to Settings » Download delivery » Emails, choose SMTP, then paste the host, port, username, password, and a sender email.
5. Click Save. Fileflare sends a verification email to your sender address.
6. Open that email within 30 minutes and click the verification link. The SMTP card flips from Pending to Enabled, and delivery emails start going out from your address.

Verify your sender address

Verification is what proves you control the address Fileflare will send from, and it’s the step most setups stall on. What to expect:

• The link expires after 30 minutes and works once. Wait longer than that (or click a link from an older verification email) and you’ll land on a “Verification link expired” page instead of the app.
• Until you verify, nothing breaks. Your order emails keep going out from Fileflare’s default address, so customers are never left without their files while you sort the connection out.
• To get a fresh link, open Settings » Download delivery » Emails and use Resend verification email on the amber “Verify your SMTP connection to finish setup” banner. Every resend issues a new link with a new 30-minute window.

Provider-specific setup

Below: provider-specific credentials and where to find them.

Postmark (recommended)

• Free tier: 100 emails/day, up to 3,000/month
• Paid from: $15/mo for 10k emails
• Verification: 1–24 hours (typically 1–2)
• Notes: Postmark hand-verifies new accounts to maintain their sender reputation, which is part of why deliverability is so good. Worth the wait.

Setup

1. Sign up for Postmark.
2. Go to Sender Signatures → Add domain or signature. Verify your domain (preferred over single email).
3. Open your server → API Tokens → Create API Key.
4. Copy the API key. In Fileflare’s SMTP settings, paste it into both Username and Password.
5. Set Host: smtp.postmarkapp.com, Port: 587 (try 25 or 2525 if 587 is blocked), Encryption: TLS.
6. Set Sender to any email address on your verified domain.
7. Save and click the verification link Fileflare emails you.

Resend

• Free tier: 3,000 emails/month, 100/day
• Paid from: $20/mo for 50k emails
• Notes: Modern API-first provider. Great DX, fast onboarding.

Setup

1. Sign up for Resend.
2. Go to Domains → Add Domain. Add the suggested DNS records to your domain.
3. Wait for the domain to show as verified.
4. Go to API Keys → Create API Key. Copy it.
5. In Fileflare, set Host: smtp.resend.com, Port: 587, Username: resend, Password: your API key, Encryption: TLS, Sender: any address on your verified domain.
6. Save and verify.

Brevo (formerly Sendinblue)

• Free tier: 300 emails/day
• Paid from: $8/mo for 5k emails
• Important: Brevo’s automatic link tracking will rewrite Fileflare’s download URLs and break them, causing customers to see “Invalid HMAC” errors. Disable link tracking in Brevo before going live.

Setup

1. Sign up for Brevo.
2. Top-right profile → Senders, Domains & Dedicated IPs → Domains → Add domain. Brevo has one-click verification for many domain providers.
3. Go to Transactional → Settings → Configuration → SMTP relay.
4. Click Generate a new SMTP key. Copy the login and the key.
5. In Fileflare, set Host: smtp-relay.brevo.com, Port: 587, Username: Brevo’s login, Password: Brevo’s SMTP key, Encryption: TLS, Sender: any address on your verified domain.
6. Save and verify.
7. Important: in Brevo, disable click/link tracking to prevent broken download links.

MailerSend

• Free tier: 3,000 emails/month
• Paid from: $30/mo for 50k emails
• Notes: Clean modern dashboard, solid deliverability.

Setup

1. Sign up for MailerSend.
2. Go to Domains → add your domain. Add the DNS records they provide.
3. Once verified, go to Email → SMTP → generate SMTP credentials.
4. In Fileflare, set Host: smtp.mailersend.net, Port: 587, Username and Password: from MailerSend’s SMTP page, Encryption: TLS, Sender: any address on your verified domain.
5. Save and verify.

Mailtrap

• Free tier: 1,000 emails/month
• Paid from: $10/mo for 10k emails
• Notes: Best known for email testing; production sending also works fine.

Setup

1. Sign up for Mailtrap and choose Email Sending (not the testing inbox).
2. Add and verify your domain via DNS records.
3. Open Sending Domains → your domain → SMTP/API integration.
4. Copy the SMTP credentials they show.
5. In Fileflare, set Host: live.smtp.mailtrap.io, Port: 587, Username: api, Password: your API token, Encryption: TLS, Sender: any address on your verified domain.
6. Save and verify.

SendGrid

• Free tier: none (free plan retired)
• Paid from: $19.95/mo for 50k emails
• Important: SendGrid’s SMTP API key has a 5,000-email lifetime cap. Once you hit it, the key stops working — you’ll need to regenerate. For high volume, consider Postmark or MailerSend instead, or use SendGrid’s regular API once Fileflare supports it directly.
• Also: disable click tracking in SendGrid (Settings → Tracking → Click tracking) — it rewrites Fileflare’s download URLs and breaks them.

Setup

1. Sign up for SendGrid.
2. Verify a sender domain via Sender Authentication (Settings → Sender Authentication → Authenticate Your Domain).
3. Create an API key (Settings → API Keys → Create API Key) with full access. Copy it.
4. In Fileflare, set Host: smtp.sendgrid.net, Port: 587, Username: apikey (literally the word), Password: your API key, Encryption: TLS, Sender: an email on your verified domain.
5. Save and verify.
6. Important: disable click tracking in SendGrid before sending real customer emails.

Other providers (Outlook, Yahoo, custom)

Most ESPs provide SMTP credentials. The pattern is the same: get host, port, username, password from your provider, paste into Fileflare. A few specifics:

• Outlook / Hotmail: host smtp-mail.outlook.com, port 587, TLS, your full email + an app password. Limit: ~300 emails/day.
• Yahoo: host smtp.mail.yahoo.com, port 587, TLS, your full email + an app password generated from Account Security.
• Google Workspace: Google has stopped SMTP access for new users. Use Postmark or another provider instead.

When your SMTP connection fails

Once you’re sending through your own server, a problem at your provider is a problem for your customers — so Fileflare tells you about it in two places rather than waiting for a support ticket.

In email settings, a red banner reads either SMTP verification failed (the connection never came up) or Email delivery is failing (it worked before and has stopped). The banner names the kind of failure and what to do about it, shows when it last happened, and keeps your provider’s raw error underneath as secondary detail. The five categories:

• Authentication: your provider rejected the username or password. Re-check your SMTP credentials — for most providers the username and password are an API key, and regenerating one invalidates the old value.
• Rate limited: your provider is temporarily throttling sends. Wait and retry, or check your provider’s sending limits. This one usually clears itself.
• Connection: Fileflare couldn’t reach your mail server. Check the host, port, and encryption settings.
• Recipient rejected: your provider refused that specific recipient address. This is about one customer’s mailbox, not your configuration.
• Unknown: your provider reported something Fileflare can’t classify. Check your SMTP settings and your provider’s activity log.

On your dashboard, a critical alert reading “Your order emails aren’t sending” links straight to email settings. It only shows while custom SMTP is your selected sender, and unlike most dashboard notices it can’t be dismissed — a store whose delivery emails are failing shouldn’t be able to hide that. Switch back to Fileflare’s mailer, or fix the connection, and it clears.

A successful send clears the error state, so once things are working the banners and the alert go away on their own.

Common issues

• “Invalid HMAC” error in customer download links — your SMTP provider is rewriting URLs for click tracking. Disable click / link tracking in the provider’s settings. (Especially Brevo and SendGrid.)
• “Verification link expired” — the link is good for 30 minutes and one click. Go to Settings » Download delivery » Emails and click Resend verification email, then open the new email straight away. If you clicked an older verification email out of your inbox, look for the most recent one instead.
• The SMTP card still says Pending — the connection is saved but not verified yet, so emails are still going out from Fileflare’s default address. Resend the verification email and click the link within 30 minutes.
• Verification email never arrives — check spam, then double-check the host, port, username, and password are correct. If the red SMTP verification failed banner is showing, read its category guidance first — an authentication or connection failure means the verification email couldn’t be sent at all, so there’s nothing to look for in your inbox.
• “Domain not verified” error from the provider — DNS changes can take up to 48 hours to propagate. Most providers re-check on demand from their dashboard. If your domain has DNSSEC, some providers don’t auto-detect — try manual re-check.
• Emails work in test but not for real orders — make sure the Sender address you set in Fileflare is on the verified domain. Mismatched sender = silent rejection.
• SendGrid SMTP stopped working after a few thousand sends — you’ve hit the 5,000-email lifetime SMTP key cap. Generate a new API key and update Fileflare with it. (Or migrate to a provider without this limit.)
• Connection timeout on port 587 — some networks block 587. Try ports 25 or 2525. Postmark especially supports both fallbacks.
• Customers see emails in spam — set up DKIM, SPF, and DMARC. See Improve email deliverability for the full setup.
• A dashboard alert says my order emails aren’t sending — a send through your SMTP server failed. Click Review email settings on the alert and read the banner’s category guidance (see “When your SMTP connection fails” above). The alert clears once a send succeeds.

Keep learning

• DKIM, SPF, DMARC setup for best deliverability
• Customize the email body, subject, and From name
• Email tracking (Fileflare’s built-in stats)
• Disable Fileflare’s emails entirely