My Samsung S3 messaging icon always show one unread message. See the screenshot below. I have thoroughly checked if there are any unread messages and also restarted the phone couple of times. I also removed the battery for sometime. Any clue as to what might be causing it?
Settings > Application Manager > All applications (on the top). Locate the "BadgeProvider" app and select "clear data". After that, restart the phone.
Isn't that a message on your SIM card? You should be able to access SIM card messages to see it and/or delete it.
There's a way to remove it, you need to send yourself a message from another phone and read the text message, then the "1" will disappear.
This also works for
Hope my answer helps.