Open the Control Center by swiping down from the upper-right corner of the home screen on iPhone X or later, or by swiping up from the bottom of the home screen on other models. If the cellular icon (the vertical antenna with two curved lines on either side in the upper-right tile) is gray, tap it to turn it green. If not, you’re already on the network. Some cellular plans don’t come with MMS messaging, while others may charge if you go over a certain amount. Make sure you check with your carrier to find out the specific limitations before sending an MMS message.
MMS is different from iMessage, which can be sent using a Wi-Fi signal when senders and recipients have iMessage enabled. It doesn’t use cellular data when Wi-Fi is available. Any time you send a photo or other type of multimedia message to someone with an Android, it will always be sent as MMS. If you don’t enable MMS, you can’t send multimedia messages to anyone with an Android or anyone with an iPhone who isn’t using iMessage.
Open the Settings app. Scroll down and tap Messages. Slide the “iMessage” switch to the Off (gray) position. [3] X Research source Return to the Messages app and attempt to send a text-only message to one recipient with no attachments. Did it go through? If the text-only message went through, try sending it again with the attachment. If it still doesn’t go through, it’s probably because the attachment is too big, or because your carrier limits MMS. If both SMS and MMS messages go through when iMessage is disabled, it’s likely because the recipient is using an Android but their phone number was once connected to an iPhone. Your iPhone may be attempting to attempt to send messages to their iMessage account rather than their phone number with MMS. If this is the case, have the recipient contact Apple for instructions for unliking their phone number from the previously-associated iMessage account. After testing, be sure to turn iMessage back on.
Open Settings. Tap General. Tap Reset. Tap Reset Network Settings. If you have a passcode, you will be asked to enter it.
