Troubleshooting Custom Values in MMS Workflows

Overview

Custom Values can be used to dynamically attach MMS content (such as images or GIFs) to workflow messages. Issues usually arise from incorrect URL setup, unsupported file types, or carrier size restrictions. This guide explains how to configure Custom Values for MMS, the file requirements, and how to troubleshoot when messages don’t send as expected.

Q1: How do I attach Custom Values URLs to SMS messages?

A1:

Set up your custom value URL:

• Navigate to Settings → Custom Values.

• Click + Add Custom Value and input the MMS URL you want to use.

Attach the custom value in your workflow:

• Open the workflow where the MMS will be sent.

• Locate the step where the MMS is triggered.

• Paste the custom value URL as an attachment.

Q2: What is the maximum MMS size when sending SMS messages?

A2:
Carrier size limits vary, so make sure your file does not exceed these requirements:

• AT&T: 0.6 MB

• Sprint: 1.4 MB

• T-Mobile: 1.5 MB

• Verizon: 0.675 MB

Q3: What file types are supported for MMS when sending via SMS?

A3:
The following formats are supported:

• JPEG

• PNG

• GIF

Tip: Always confirm the file is in one of these formats before uploading it to your MMS URL.

Q4: My custom value is not working when the message is sent. What should I do?

A4:

• Check for extra spaces in your custom value URL.

• Test by adding the custom value to a dummy funnel and previewing the page.

• If the MMS appears correctly, the value is working.

• Confirm the file meets the carrier’s size limit.

• Compare your MMS file size to the carrier requirements listed in Q2.

• Files larger than the carrier limit will fail to send.

Q5: How do I know if my custom value meets the carrier’s size requirements?

A5:

• Check the file size of your MMS attachment before sending.

• Compare against the carrier limits (see Q2).

• If the file is larger than the maximum, compress or resize it before use.