Everyone forgets their Galaxy S4, but the same process works on many other Samsung devices too. Android 5.0 Lollipop and security How to use Android Device Manager
A hard-reset left me unable to complete the initial setup, as the account manager kept stopping too. My S3 was stock standard, not rooted or running any custom firmware. I was able to fix the problem, and I'd like to share my solution. Download Samsung's "Kies" software.
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how to factory reset samsung galaxy s3 mini