Do these 3 things before closing this tab:
1Scan for outdated or missing drivers - takes under a minute2Clear out junk files and repair common Windows errors3Fix the driver behind crashes, sound loss and screen glitchesTo erase a usable, unlocked Galaxy S21 5G, open Settings > General management > Reset > Factory data reset, review what will be removed, then confirm Reset and Delete all. If the phone is frozen, locked, or missing, the right option depends on whether it can be accessed and whether it is online. A factory reset erases personal data; it is not the same as a forced restart.
Choose the reset method that fits your situation
| Method | When it fits | Erases personal data? | Requirements and caveats |
|---|---|---|---|
| Factory data reset in Settings | The phone is usable and you can unlock it. | Yes | May require the screen-lock credentials and, if signed in, the Samsung account password. [Samsung’s reset instructions] |
| Recovery-menu reset with device buttons | You cannot access Settings, including when locked out. | Yes | Samsung UK’s procedure calls for connecting the powered-off phone to a computer by USB. Google account verification may be required afterward. [Samsung UK recovery instructions] [Google Factory Reset Protection information] |
| Erase through SmartThings Find | The phone is lost, online, and configured for remote control. | Yes | Requires Wi-Fi or mobile data, a Samsung account signed in on the device, and remote control and remote unlock enabled. [Samsung UK SmartThings Find instructions] |
| Reset settings or network settings | You want to troubleshoot without deleting apps or personal data. | No | These reset selected settings rather than wiping the phone. [Samsung’s reset instructions] |
Samsung notes that menu names and screens can differ by model and software version. If the labels on your S21 differ, follow the options shown on your device and consult Samsung support for your region.
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Before a factory reset: protect your data and check account access
- Back up what you need. A factory reset removes personal data, and Samsung warns that personal information may not be recoverable. Copy important photos, videos, documents, and other files before proceeding if you can still use the phone. [Samsung’s reset instructions]
- Have the account credentials ready. A Samsung account signed in on the device may need its password to complete a Settings reset. A reset performed outside Settings can trigger Google Factory Reset Protection, which may require the Google account previously registered on the phone during setup. A reset does not bypass ownership checks. [Samsung’s reset instructions] [Google Factory Reset Protection information]
- Consider removable storage only if applicable. Samsung’s general Galaxy guidance says to decrypt an encrypted microSD card before resetting; otherwise, the device may not read it afterward. Galaxy S21 5G configurations and regions vary, so do not assume every S21 has a microSD card. Samsung also says network access is required to log out of a Samsung account during reset. [Samsung’s reset instructions]
Reset a usable Galaxy S21 5G in Settings
- Open Settings > General management > Reset > Factory data reset.
- Review the list of accounts, apps, and data affected by the reset. Back out if you still need to make a backup.
- Tap Reset, authenticate if prompted, then tap Delete all to confirm.
- Allow the phone to erase its data and restart. Complete setup afterward using the required account credentials.
This is the straightforward route when you can use and unlock the phone. Samsung notes that screen labels can vary by software version. [Samsung’s reset instructions]
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Use recovery mode if Settings is unavailable
Samsung UK documents a button-based recovery reset for devices that cannot be reset through Settings. Its instructions say to power off the phone, connect it to a computer by USB, then open recovery. The guide explicitly includes the S21 in its examples for phones without a physical Home button, but its listed button sequence uses the word “Home” in a way that is ambiguous for that group. If the stated sequence does not open recovery on your S21, consult Samsung’s current device-specific support or manual rather than guessing another combination. [Samsung UK recovery instructions]
#1 Best Overall
- Display: 6.2" AMOLED display with 120Hz refresh rate and 1300 nits brightness for vivid visuals and smooth scrolling.
- Camera: Rear dual camera system with 64MP main and 12MP ultrawide lenses for stunning photos and videos.
- Memory: 128GB internal storage and 8GB RAM for plenty of apps and files.
- Connectivity: 5G capable with support for GSM, CDMA, and Wi-Fi networks.
- Battery: 4000mAh battery provides all-day power for your daily needs.
- Power off the phone and connect it to a computer with a USB cable, as Samsung UK’s instructions specify.
- Use the device-specific buttons to open recovery, following Samsung’s current instructions for your exact device and software.
- In recovery, use the volume buttons to highlight Delete all user data or Wipe data/factory reset, then press the Power button to select it.
- Confirm the wipe. Wait for Data wipe complete, then select Reboot system now.
The phone will restart and begin setup. Because this reset is performed outside Settings, be prepared to verify the Google account previously registered on the device. [Samsung UK recovery instructions] [Google Factory Reset Protection information]
Erase a lost phone with SmartThings Find
Remote erasure is an option only if the phone is online and was configured for it. Samsung UK says the device must be connected to Wi-Fi or mobile data, signed in to a Samsung account, and have remote control and remote unlock enabled. The account owner signs in to SmartThings Find, selects the device, and chooses Erase data; identity verification may be required. [Samsung UK SmartThings Find instructions]
Rank #2
- The Galaxy S21 FE sports a sleek polycarbonate back with a premium matte finish that resists fingerprints and feels smooth in hand, giving it a stylish yet practical design.
If the phone is offline or those remote controls were not enabled, this method may not be available. Remote erasure also deletes personal data and does not remove account or ownership protection.
Troubleshoot first if your goal is to fix a frozen or boot-looping phone
A factory reset is a last resort when troubleshooting startup problems because it erases data. Samsung recommends working through lower-risk steps first, including restarting, charging with a Samsung-certified charger and cable if the battery may be drained, checking for software updates, and testing in Safe mode to see whether a third-party app is responsible. If the problem continues even in Safe mode, Samsung says a hardware issue is likely and directs users to service support. [Samsung startup and boot-loop guidance]
Quick Recap
Rank #4
- This pre-owned product has been professionally inspected, tested and cleaned by Amazon qualified vendors.
- This product is in "Excellent condition". The screen and body show no signs of cosmetic damage visible from 12 inches away.
- This product will have a battery that exceeds 80% capacity relative to new.
Rank #3
- 6.2 inch, 1080 x 2400 pixels, Dynamic AMOLED 2X, 120Hz, HDR10 plus, 1300nits, 4000mAh Battery
- 256GB ROM, 8GB RAM, No SD Card Slot, Qualcomm SM8350 Snapdragon 888 5G (5 nm), Octa-Core, Adreno 660
- Rear Camera: 64MP, f/2.0 plus 12MP, f/1.8 plus 12MP, f/2.2, Front Camera: 10 MP, f/2.2, Android 11, One UI 3.1
- 2G: GSM 850/900/1800/1900, CDMA 800/1900, 3G: HSDPA 850/900/1700(AWS)/1900/2100, CDMA2000 1xEV-DO, 4G LTE: 1/2/3/4/5/7/8/12/13/14/18/19/20/25/26/28/30/38/39/40/41/46/48/66/71, 5G: 2, 5, 25, 41, 66, 71, 260, 261 SA/NSA/Sub6/mmWave - Single SIM
- US Model. Compatible with Most GSM and CDMA Carriers like T-Mobile, AT andamp;T, MetroPCS, etc. Will Also work with CDMA Carriers Such as Verizon, Sprin
- Want to preserve data while troubleshooting? Try Settings > General management > Reset and choose an applicable settings-only or network-specific reset instead of Factory data reset. Samsung says these options do not erase apps or personal data. [Samsung’s reset instructions]
- Phone unresponsive? A forced restart is a power-cycle step, not a factory reset. Samsung’s cited US troubleshooting article discusses restart from the Quick panel but does not give an S21-specific forced-restart button duration there, so check current S21-specific instructions rather than relying on a guessed timing. [Samsung startup and boot-loop guidance]
- Still boot-looping after troubleshooting? Consider a factory reset only after weighing data loss and account verification. If the issue persists in Safe mode, seek Samsung service support rather than repeatedly wiping the phone. [Samsung startup and boot-loop guidance]
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