Diobox takes extensive measures to ensure high email deliverability, though it’s not possible to guarantee that every email will be opened or seen by the recipient. Below are common scenarios where an email may be sent but not received:

Blocked Message

Corporate email policies sometimes block or delay emails from new or unknown domains, especially those containing links. This can often happen when sending to business email addresses.
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Temporarily Issues

Valid email addresses can occasionally reject emails temporarily (soft bounce). Common causes include a full mailbox, server overload, or ongoing server configurations that prevent message acceptance.
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Spam or Promotion

Emails may end up in the Spam or Promotions folder due to several factors:

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Compelling Subject Lines

Use clear and relevant subject lines that resonate with your audience. Personalization and action-oriented language can improve open rates.

Optimize Email Content to Avoid Spam Triggers

Avoid spammy words (like “Free” or “Guaranteed”) and minimize the use of all caps, excessive images, or special characters. A balanced mix of text and images helps emails appear legitimate and enhances readability.

Include Both Images and Text

Use a balanced combination of images and text in your email content to avoid spam filters. If designing your own images, keep them under 800 pixels in width to ensure fast loading. Always include some text outside the image, even if the image contains text within it, as this helps email clients better interpret the content and reduces the likelihood of being flagged as spam.

Personalize Content:

Use merge tags to customize your emails by including the recipient’s name or other personal details, such as “Dear [Name].” Personalized content improves engagement and reduces the chances of emails being marked as spam.

Use Custom Email Domain

To further improve email delivery, consider using the Custom Email Domain feature. Sending emails from your corporate domain helps authenticate the sender, increasing the chances of successful delivery. This is particularly effective if recipients are familiar with your organization’s domain have received emails from you in the past.
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