Good afternoon DZMan. I am sorry to hear that you are still having issues with your computer recognizing your Galaxy S3. I agree with your conclusion that since it works on your other two S3's, it has to be a device issue. I would hope that a factory reset would fix it, but if you have tried it twice by following these steps, http://vz.to/LfV00q, I would hate to do have you do it a third time. The factory reset is our last step in troubleshooting as this usually rids the device of any corrupt files that may be causing the issue. If you have tried the factory reset twice, then I would like to look into replacement options. Any device you purchase through us comes with a one year manufactuer's warranty. So as long as you've had the device for less than a year and there is no physical or water damage, then we can replace the device for you at no cost. If you are outside of the warranty, do you know if you have insurance on the device? We can look into placing an insurance claim as well. Please let me know if you need any additional assistance.
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