Are you sending a pic in the group message? If so, it's possible that for some receiving the message the pic size is larger than the carrier or their device can receive and that might be why they receive a blank message. I haven't had the issue with my iPhone 4, but when I was using my BB I would have that problem whenever I took a pic on it and tried to send it to AT&T customers. If I didn't resize the pic and it was at it's highest setting then the pic was too large and they would receive a blank pic. Once I resized and re-sent they received it fine. This may or may not be the issue concerning the 4s, but it's a possibility. If you send the same pic to that person in an individual message instead of a group one do they receive it? If not, the size may be the issue. If you open that same pic on your computer you will see that the default size is quite large. If their provider is throttling data or something they may restrict the sizes of files that will be accepted. This still isn't an absolute answer to your problem but like I said, it's something that could be part of the issue.
There might be an issue directly related to group messaging as related to the 4s. If you have tried a reset/restart/restore (restore without using a saved backup if you try this option to see if that helps and to make sure there isn't something corrupt with the backup) then I would suggest contacting VZW to see if they can help...although based on other posts that doesn't seem to help much. You might also try contacting Apple to see if they have any suggestions
I would like to thank everyone for their input. rob0424, I know how much of an inconvenience this issue is because group text messaging saves time and helps you get a message out to a lot of people at once. I researched your issue in more detail and didn't find this was reported as an issue. I don't show there is a limit for how many contacts you send a text or picture to without having an issue but I suggest limiting the amount of people you send it to. This may help eliminate the problem. I also recommend clearing your cache and browser history periodically and also deleting unwanted messages periodically. Listed below are some steps.
Steps to clear Cache and broswer histoy:
Touch Media Center.
Touch Manage Memory.
Touch the desired items to be cleared using the 5-way navigation pad.
A indicates that the item is selected.
With the desired items selected, touch Clear.
Thanks for the clarification. Do you have group messaging turned on? Basically group messaging allows the other users to see each others' responses and sends the message as an MMS. With group messaging turned off, it send the message as a text and the responses only go to you. Try changing the setting to see if the results are the same (Settings>Messages>Group Messaging). Do you notice if it is the same person each time that gets a blank SMS or the same carrier? If you have any special characters, graphics, or signature, make sure to remove those and retest.
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