Reasons for communication errors

Error Persistence

Actionable for tenants

Time of occurrance

Reason Code / Status

Communication channel

Explanation

Recommended action

(If possible)

Permanent

Yes

Before sending

INVALID_EMAIL_ADDRESS

Email

The email address failed validation checks (e.g., missing "@"). It will never work until fixed.

Verify the email with the customer.

Permanent

Yes

Before sending

INVALID_MOBILE_NUMBER

SMS

The number is wrong or incomplete. It will never be delivered in its current state.

Verify the mobile number with the customer.

Temporary

Yes

After sending

BOUNCE_TRANSIENT_MESSAGE_TOO_LARGE

Email

The specific message was rejected because it’s too big. The address is fine, but the content must be reduced.

Change the message content at collect.AI.

Temporary

Yes

After sending

BOUNCE_TRANSIENT_CONTENT_REJECTED

Email

The mail server didn't like the content (spam filters). The address is valid, but the message needs editing.

Change the message content at collect.AI.

Temporary

Yes

After sending

BOUNCE_TRANSIENT_ATTACHMENT_REJECTED

Email

A specific attachment type was blocked. The address is valid; just change the file format.

Check the uploaded attachment of the case a collect.AI.

Permanent

No

After sending

BOUNCE_PERMANENT_MAILBOX_UNAVAILABLE

Email

The recipient's server says the address doesn't exist. Stop sending to this address immediately. collect.AI automatically adds the contact to the suppression list.

-

Permanent

Partially, yes

After sending

BOUNCE_PERMANENT_ON_SUPPRESSION_LIST

Email

The address is already blocked by collect.AIs system to protect your reputation.

Needs a manual removal from the suppression list in the collect.AI Management portal if the bounce reason could be resolved manually.

Permanent

No

After sending

BOUNCE_PERMANENT_GENERAL

Email

A hard bounce where the provider didn't specify a code. collect.AI automatically adds the contact to the suppression list.

-

Temporary

No

After sending

REJECTED / REJECTD

SMS

The carrier has actively refused the message (e.g., due to a block/blacklisting of the number or invalid destination). We’ll retry it again if there is another message to be send.

-

Temporary

Yes

While sending

HANDOVER_ERROR

Both

A technical "handshake" failure between collect.AI and the messaging provider. This is an infrastructure issue and usually resolved on it's own by auto-retries.

-

Temporary

No

After sending

BOUNCE_TRANSIENT_MBX_FULL

Email

The inbox is full. This is usually temporary. If SES is used as email sending provider, it will retry for some time. The next email communication will try the to send an email again.

-

Temporary

No

After sending

BOUNCE_TRANSIENT_GENERAL

Email

A general connection or routing issue. SES will retry automatically for a period of time. We’ll retry it again if there is another message to be send.

-

Permanent

Yes

After sending

UNDELIV / FAILED

SMS

Delivery failed at the network level. This can happen if the phone is off or in a dead zone.

Verify the mobile number with the customer.

Permanent

Yes

After sending

EXPIRED

SMS

The message sat in the network queue too long without the handset connecting.

Verify the mobile number with the customer.