# SMS and MMS messaging

> Send an image or PDF with the prepared MMS message, review delivery, and help customers subscribe or unsubscribe.

Language: en-US. Product guide: https://agencymesh.app/help/sms-messaging/.

Last reviewed October 1, 2026 by AgencyMesh Product Support · Checked against release 2026.10

Send one image or PDF with your office’s prepared message. The Message field is read-only; Messaging does not compose custom text.

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## Send an MMS

**Where:** Text Messages > [Messaging](https://app.agencymesh.app/sms/messaging).

**Dashboard > Communications > Send MMS** uses the specific office selected in **Phone / Office**. Choose an office instead of **All Offices**.

1. Enter the 10-digit US **Phone Number** and choose **Office**.
2. Choose one **Attachment** and click **Send**. Find the result in **Recently Sent Messages**.

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## Choose a supported attachment

An attachment is required. Choose another file in **Attachment** to replace it before sending; there is no attachment preview or recall.

| Item | Guidance |
| --- | --- |
| Images | One JPEG, PNG, or GIF, up to 5 MB. |
| PDF | One PDF, up to 600 KB. |

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## Check a sent message

**Where:** [Messaging](https://app.agencymesh.app/sms/messaging) > Recently Sent Messages.

Use **Message ID** when reporting a delivery problem. For older records, use **Text Messages > Search**.

1. Filter with **Search sent messages…**; use **Refresh messages now** to update the list.
2. Click **View** on the message to see its body, attachments, **Status**, **Error Code**, and **Error Message**.

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## Help a customer subscribe or unsubscribe

Under **How to Manage Opt-in**, use the displayed sending number: customers text **START** to subscribe or **STOP** to unsubscribe.

Use **Copy** beside **Shareable Subscription Link** to share the subscription page. The customer must send the opt-in text; opening the link alone does not subscribe them.

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## Resolve a failed send

Open the message’s **View** details and use **Error Code** / **Error Message** to identify the problem. Correct the number, subscription, or attachment before sending again. Check the existing record first if the first result was unclear.

## Related guides

- [Search message history](https://agencymesh.app/help/sms-search.md)
- [Calls, SMS, and customer messaging](https://agencymesh.app/help/calls-and-messaging.md)
- [Files, dates, and limits](https://agencymesh.app/help/files-dates-and-limits.md)