My iphone4s is a Unicom card. Why can't I send photos by SMS?

According to your description, you can refer to the following information:

1. I suggest you change your mobile phone and test the Unicom card in your hand first. If your card can't be used normally, don't rule out the problem of mobile phone card; In addition, if the card is cut, it may also lead to the damage of the mobile phone card and affect the use. In that case, I suggest you change your card at the local Unicom business hall with valid documents. If your mobile phone card can be used normally, there is no problem with your mobile phone. In addition, if you have a locked version abroad, after the system upgrade, it will affect the use because the card does not match the system. You can consult the mobile phone after-sales or mobile phone staff for details.

2. In addition, if you have problems with texting, I suggest you set the number of the SMS center.

3. If you are in the weak signal coverage area of Unicom, it may affect your use.

If it is not for the above reasons, I suggest you take your mobile phone and mobile phone card to Unicom's own business hall or mobile phone after-sales center to help you test it.