Here we explain each type of email verification result and suggest what to do, depending on how you plan to use the address.
Undeliverable
These addresses aren’t valid and will cause a bounce. They’re a direct risk to your sender reputation and you should never use them.
Undeliverable: Invalid syntax
There’s an error in the address. It may have been typed incorrectly.
Suggested action: Don’t send emails to this address, as they will bounce. Try to find an updated address through other channels.
Undeliverable: Invalid domain
The domain of this email isn’t set up to receive messages.
Suggested action: Don’t send emails to this address, as they will be rejected. Look for a valid address by other means.
Undeliverable: Mailbox doesn’t exist
The mailbox doesn’t exist on the server. The address may have expired or been mistyped.
Suggested action: Don’t send emails to this address, as they will bounce. Try to find an alternative address through other channels.
Risky
These addresses carry different levels of uncertainty. Some may look valid but perform poorly; others may bounce, generate spam complaints or affect your sender reputation. Proceed with caution.
Risky: Full inbox
The inbox is full and may no longer be in use. If space isn’t freed up, emails sent to it will bounce.
Suggested action: Remove this address from your lists and verify it again later. Consider looking for an alternative.
Risky: Account disabled
The account has been deactivated, possibly due to inactivity or for security reasons. While it stays disabled, messages sent to this address will bounce.
Suggested action: Remove this address from your lists and check it again later. If it isn’t reactivated, consider looking for an alternative address.
Risky: Connection error
The server isn’t available right now. This could be due to maintenance or network issues. If the problem continues, messages may be rejected.
Suggested action: Try verifying again later. If you still get no response, consider using an alternative address.
Risky: Disposable email
This type of email address is created to avoid sharing a real address. It’s usually used once and then thrown away.
Suggested action: Don’t send messages to this address. Remove it from your lists and replace it with a more reliable one.
Risky: Catch-all domain
The server accepts email sent to any address on the domain, even ones that don’t exist. For example: 34sdfkje@azulsistemas.es. There’s no guarantee the address belongs to a real person.
Suggested action: Remove it from your marketing lists, especially if it shows no signs of engagement. Use it with caution, and only for non-critical messages.
Risky: Role-based email
This may be a shared email address used by several people or, occasionally, by just one. These inboxes tend to generate more spam complaints, as messages may not be relevant to every recipient.
Suggested action: Remove it from your marketing lists. It can still be used for support or transactional messages.
Risky: Timeout
The system is waiting but hasn’t received a response from the server yet.
Suggested action: Extend the timeout period and try the verification again. If you still get no response, consider using an alternative address.
Deliverable
This email is active and can receive messages.
Suggested action: These are the safest contacts to send to. They’re ideal for transactional messages and reliable for marketing, newsletters and promotions.
Try our free email verification tool to find out whether an email can receive messages.