Samsung Galaxy S8 - Manual (Page 178)

Settings 171
Reset
Reset device and network settings. You can also reset
your device to its factory defaults.
Reset Settings
You can reset your device to its factory default settings,
which resets everything except the security, language,
and account settings. Personal data is not affected.
1. From a Home screen, swipe up to access Apps.
2. Tap Settings > General management > Reset >
Reset settings.
3. Tap Reset settings, and confirm when prompted.
Reset Network Settings
You can reset Wi-Fi, Mobile data, and Bluetooth
settings with Reset network settings.
1. From a Home screen, swipe up to access Apps.
2. Tap Settings > General management > Reset >
Reset network settings.
3. Tap Reset settings, and confirm when prompted.
Factory Data Reset
You can reset your device to factory defaults, erasing all
data from your device.
This action permanently erases ALL data from the
device, including Google or other account settings,
system and application data and settings, downloaded
applications, as well as your music, photos, videos, and
other files. Any data stored on an external SD card is
not affected.