WP Mail SMTP plugin review and common issues

WP Mail SMTP improves email deliverability by using authenticated SMTP, but spam placement also depends on DNS configuration and sender reputation. After configuring WP Mail SMTP, verify: (1) SPF record — add your SMTP provider’s SPF entry to your domain DNS (your SMTP provider’s documentation lists the exact record to add); (2) DKIM — enable DKIM signing in your SMTP provider account and add the DKIM DNS record to your domain; (3) DMARC — add a DMARC policy record to gradually build sender authentication. Check your sending domain’s reputation at Google Postmaster Tools and MxToolbox.

Google’s OAuth requires an authorized redirect URI that matches your WordPress site URL exactly. If your site URL changed (HTTP vs HTTPS, www vs non-www, domain change), the redirect URI in your Google Cloud Console project will not match. Go to Google Cloud Console → OAuth 2.0 Clients → your client → Authorized redirect URIs and add the redirect URI shown in WP Mail SMTP’s settings. URI mismatch is the most common cause of Gmail OAuth failures.

WP Mail SMTP routes all WordPress emails including WooCommerce order emails. If order emails stopped: (1) use WP Mail SMTP → Tools → Test Email to verify the SMTP connection is working at all — if the test email fails, fix the SMTP configuration first; (2) in WooCommerce → Settings → Emails, verify order confirmation emails are enabled and the recipient is set correctly; (3) if using WP Mail SMTP Pro, check the Email Log for WooCommerce order emails — the log shows whether emails were accepted by the SMTP service or failed with an error code.

Multiple mailer routing is a Pro feature. In WP Mail SMTP Pro → Settings → Additional Connections, add a second SMTP connection. Then go to Routing Settings and configure rules: for example, route emails from WooCommerce (identified by From Email matching your WooCommerce notification email) via the primary transactional mailer (Amazon SES), while routing contact form notifications via SendGrid. This ensures order-critical transactional emails use your highest-reliability mailer.

Yes. In WP Mail SMTP → Settings → General → From Email, set your preferred sending address (e.g., orders@yourdomain.com or noreply@yourdomain.com). Enable “Force From Email” to override any “From” address set by plugins (WooCommerce, contact form plugins). Similarly, configure the “From Name” and enable “Force From Name” to standardize the display name across all WordPress emails regardless of which plugin generates them.

If email logging, multiple mailer connections, and failure alerts are needed at no cost, FluentSMTP provides all of these for free. WP Mail SMTP’s advantage is its more polished setup wizard, dedicated support for email delivery issues (Pro), and exclusive Microsoft 365 one-click OAuth setup. For non-technical site owners who may need support during a deliverability crisis, WP Mail SMTP Pro at $49/year is worth the investment. For technically confident users, FluentSMTP delivers comparable functionality at zero cost.

WP Mail SMTP can standardize the “From” address for all WordPress emails. By default, WordPress uses the admin email address, which may not match your sending domain or brand name. Configure a custom From Email (e.g., no-reply@yourdomain.com) in WP Mail SMTP settings to ensure all WordPress-generated emails have a consistent, professional sender identity regardless of which plugin generates them.

Yes, that can happen, especially on older sites with many plugins. This usually happens when the plugin, theme, and add-ons are updated out of sequence. In most cases, testing on staging catches the issue before it reaches the live site. From experience, backups and changelog reviews save a lot of cleanup time.

Start by checking whether another plugin already does the same job. In most cases, overlap is what creates avoidable conflicts and performance issues. A common issue is installing a plugin because it looks convenient without checking the stack first. From experience, a short compatibility review avoids most of the pain later.