I took my unlocked S8 to an authorized service center and they told me there was nothing they could do. Said the reason my phone won't send SMS/MMS is deep into the configuration. Researching shows that the unlocked S8's don't play nice with Verizon in partcular. There are software configuration problems with the unlocked version. Took a gamble and learned how to switch the CSC code to VWZ and flash the firmware to a Verizon version. Now my S8 works perfectly; sends SMS/MMS messages no problem. I'm not thrilled with all the Verizon spamware in the software but that's preferable to haveing an expensive phone I couldn't use. I don't know why Samsung even bothers to sell the unlocked version phones since they are very hit and miss as to whether they will work or not. And even when they do, often times there are features missing on the unlocked phones such as wifi calling and so forth. I like the phone but I'll never buy an unlocked Samsung again
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My unlocked S8 does this too; can't send SMS or MMS messages. Very frustrating. I'm with Boom which uses the Verizon network and they spent a LOT of time working with me trying different things but no love. At the end the CSR threw up their hands and said it must be the device. They have had a number of issues with unlocked S8 I was told. The Verizon version S8 is fine because the software is tuned for the network it seems. For example, people talk about "message center" and checking the number but the unlocked S8 doesn't have a message center. What to do?
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