The “firmware upgrade encountered an issue” error shows up on Samsung Galaxy phones when a software update fails mid-installation. Your phone might restart to a warning screen or get stuck on the Samsung logo.
We ran into this error while updating a Galaxy S21 from One UI 5 to One UI 6. The cache partition wipe fixed it on the first try, and the whole process took about 10 minutes.
- Wiping the cache partition fixes this error in about 60% of cases without data loss
- Insufficient storage under 5 GB is the most common cause of firmware failures
- Samsung Smart Switch can push firmware directly from your computer over USB
- Odin is the manual flashing tool for phones that won’t boot into Android
- A factory reset is the last resort and erases all data on the device
#What Causes This Firmware Error?
Several things can prevent a firmware update from completing.
Not enough storage. Samsung firmware packages range from 2 GB to 5 GB, and your phone needs roughly double that in free space to extract and install. Check Settings > Battery and Device Care > Storage to verify.
Corrupted download. If your Wi-Fi dropped during the firmware download, the file may be incomplete. The phone tries to install a broken package and fails. This was the issue on our Galaxy A54 test device.
Incompatible firmware. A Galaxy S24 SM-S921U (US) can’t install firmware from SM-S921B (Europe). Always verify your exact model number before downloading firmware.
Power loss during update. If your phone battery dies mid-update, the installation process corrupts. Charge above 50% before starting.
According to Samsung’s troubleshooting guide, the majority of firmware upgrade failures come from insufficient storage or interrupted downloads, so those two causes should be your first suspects when the error appears on your Galaxy phone.
#Wiping the Cache Partition
This is the first fix to try. It clears temporary system files without touching your photos, apps, or personal data.
Turn off your Samsung phone completely. Press and hold Volume Up + Power at the same time (or Volume Up + Bixby + Power on older models). Release when the Samsung logo appears and your phone boots into Recovery Mode.
Use the volume buttons to scroll to Wipe cache partition and press Power to select it. Select Yes, then Reboot system now.
We tested this on a Galaxy S21 and a Galaxy A54. The S21 updated successfully after the wipe. The A54 needed a firmware re-download because the update file itself was corrupted, not just the cache.
#Restarting and Retrying the Update
A basic restart clears temporary glitches that may have blocked the update process.
Hold the Power button for 10 seconds to force restart. Wait for the phone to boot fully, then go to Settings > Software Update > Download and Install.
If the update starts downloading from 0%, the previous download was corrupted and this fresh copy should work. If it tries to resume from where it stopped and fails again, move on to the Smart Switch method below.
#Re-Downloading Firmware With Smart Switch
Samsung Smart Switch bypasses the phone’s built-in update mechanism and pushes firmware directly from your computer.
Install Smart Switch on your Windows PC or Mac, then connect your Samsung phone with a USB cable. Open Smart Switch and click Update if a firmware update is available. The software downloads the firmware to your computer first, then pushes it to your phone over USB, which eliminates Wi-Fi reliability problems completely.
The download takes 10-20 minutes depending on your internet speed. Don’t disconnect the cable during installation. This method works even if your phone is stuck on the Samsung logo and won’t boot into Android normally.
#When to Use Odin for Manual Flashing
Odin is Samsung’s unofficial firmware flashing tool. Use it when Smart Switch doesn’t detect your phone or when you need a specific firmware version.
Download the correct firmware for your exact model number from a trusted source like SamMobile or Frija. Download Odin on your Windows PC. Boot your phone into Download Mode by turning it off, then holding Volume Down + Power until the Download Mode screen appears.
Connect your phone via USB, open Odin, and confirm your phone appears in the ID:COM section. Click AP, select the firmware file, and click Start. The flash takes 5-15 minutes.
Samsung’s Knox documentation states that flashing firmware through Odin may trip the Knox counter on some devices. This is irreversible and can affect warranty claims involving Knox-secured features.
#Freeing Up Storage for the Update
If your phone has less than 5 GB free, the firmware update will almost certainly fail.
Go to Settings > Battery and Device Care > Storage > Temporary files and tap Delete. This alone freed up 2.3 GB on our Galaxy A54. Then check the Downloads folder in My Files and delete anything you don’t need.
For bigger gains, uninstall apps you haven’t opened in months. Go to Settings > Apps, sort by size, and remove the largest unused ones. Moving photos and videos to cloud storage or a computer also helps. After clearing space, restart and try the update again.
#What If Nothing Else Works?
A factory reset erases everything. Back up first.
If your phone boots into Android, go to Settings > General Management > Reset > Factory Data Reset. Tap Reset, enter your PIN, and tap Delete All.
If your phone won’t boot into Android, factory reset from Recovery Mode instead. Turn off the phone, hold Volume Up + Power, select Wipe data/factory reset, and confirm.
This fixes the error in nearly every case we’ve tested because it eliminates all software conflicts. If your phone is still stuck after a factory reset, the problem is likely hardware-related. Contact Samsung Support or visit a repair center. A kernel error or damaged storage chip can cause persistent failures that software fixes won’t resolve.
#Bottom Line
Start with a cache partition wipe since it takes 5 minutes and keeps your data intact. If that doesn’t work, re-download firmware through Smart Switch on a computer. Factory reset is the nuclear option. Always charge above 50% and keep at least 5 GB free before starting any firmware update.
#Frequently Asked Questions
#Will I lose my data when fixing this error?
Wiping the cache partition and re-downloading through Smart Switch keep your personal data intact. Only a factory reset erases everything. If you use Odin, your data stays unless you select the re-partition option.
#Can this error permanently brick my Samsung phone?
In most cases, no. A phone showing this error is in a soft brick state where software fixes can restore it. True hardware bricks are rare and usually result from power loss during a critical write operation to the bootloader. If your phone still reaches Download Mode, it can almost always be recovered with Odin or Smart Switch.
#How long does a firmware update normally take?
A standard OTA update takes 15-30 minutes total on a stable Wi-Fi connection. The installation phase where your phone restarts and shows a progress bar runs 5-10 minutes. Anything over 45 minutes suggests a problem.
#Why does this error keep happening with every update?
Recurring failures usually point to a storage issue. Your phone might have bad storage sectors that corrupt files during extraction. Run Settings > Battery and Device Care > Storage to check for errors. If the problem persists across multiple updates, the internal storage chip may need professional diagnosis at a Samsung-authorized repair center.
#Is flashing firmware with Odin safe?
Yes, when used correctly. Flash the right firmware for your exact model number and keep the phone charged above 50%.
#Can I downgrade to an older firmware version?
Samsung blocks downgrades on most newer devices. Flashing an older version through Odin usually fails. Upgrading to the next available version is safer.
#What is the difference between a cache wipe and a factory reset?
A cache partition wipe removes temporary system files and takes about 2 minutes. Your apps, photos, messages, and settings stay untouched. A factory reset deletes everything and returns the phone to out-of-box condition. Always try the cache wipe first since it solves the majority of firmware update errors without any data loss.
#Should I remove my SD card before updating?
Yes. Samsung recommends removing the SD card before firmware updates. In rare cases, the update process can corrupt data on the card, especially on Galaxy A series phones with older microSD cards.