Red box error

See Setting up mail

What email settings do you have in the Mail tab panel?

To protect personal data, hiding email addresses in the settings or replacing them with dummy addresses is strongly advised. You can also include screenshots.

Here’s my settings: https://cavca.org.uk/wp-content/uploads/2022/09/cf7-problem.png

What other plugins and theme do you use on the site?

My theme is Apress and I’m using these plugins:

Advanced Editor Tools
Akismet
All In One SEO
All In One WP Security
Amelia
Anti-Malware Security and Bruce-Force Firewall
Classic Widgets
Complianz
Custom Post Type Permalinks
Duplicate Page
Easy Google Fonts
Email Encoder
Envato Market
Honeypot for CF7
Image SEO
One Click Accessibility
One Click SSL
Security Ninja
Shortcodes Ultimate
Site Kit by Google
Social Snap Lite
SVG Support
Ultimate Addons for WPBakery Page Builder
UpdraftPlus
WP Mail SMTP
WPBakery Page Builder

FYI – I’ve already tried disabling plugins related to security or cache, but that hasn’t made any difference.

Try switching to the default theme and deactivating all plugins excluding Contact Form 7, Akismet, and Classic Widgets.

Why you are advised to deactivate plugins and switch to the default theme.

I’ve done that, and it’s still got the same red box error message.

See FAQ > I get an error message with a red border. So, how can I solve this?

I’m already using WP Mail SMTP to direct messages via Gmail – would that indicate that my host is the problem?