Encryption failure on Android is one of the most annoying errors that a user can encounter. It blocks access to data, makes the device unusable and is often accompanied by messages like "Encryption interrupted", "Failed to decrypt" or endless loading with the manufacturer's logo. Unlike ordinary system glitches, this problem is related to data protection at the Android kernel level, and its solution requires an accurate understanding of the operating mechanisms File-Based Encryption (FBE) or Full-Disk Encryption (FDE).

In this article we will look at why the failure occurs encryption, how to recognize it in the early stages, and what to do depending on the severity of the situation - from a simple restart to complex manipulations through fastboot or recovery. We will pay special attention devices with Qualcomm and MediaTek chips, where encryption algorithms may differ, and also consider cases where data recovery is possible even after a “brick”. If your smartphone is frozen on the screen with the message «Encryption unsuccessful» —don’t panic: in 70% of cases the problem can be solved without contacting a service center.

What is encryption on Android and why do you need it

Data encryption on Android is the process of converting information on the device into an unreadable format using cryptographic algorithms. The main goal is to protect personal data (photos, messages, passwords) from unauthorized access if the phone is stolen or lost. Starting from Android 6.0 Marshmallow, encryption has become mandatory for all devices that support Adoptable Storage (the ability to use an SD card as internal memory).

There are two types of encryption:

  • 🔒 Full-Disk Encryption (FDE) - encrypts the entire disk (used before Android 7.0). If it fails, it often requires a full reset.
  • 📁 File-Based Encryption (FBE) — encrypts files individually (with Android 7.0+). More flexible, but vulnerable to errors when updating the software.

The encryption process starts automatically when:

  • 📱 The first time you turn on a new device (on some models Samsung, Google Pixel, OnePlus).
  • 🔄 Android update (especially when upgrading to a new version, for example, from 12 to 13).
  • 🔐 Setting a custom PIN code or password (on devices with FBE).
⚠️ Attention: On devices with MediaTek Helio (for example, Redmi Note 8 Pro, Realme 6) encryption failures occur 3 times more often due to implementation features storage drivers. Before updating the software, check the firmware reviews for your model.

Causes of encryption failure: from software bugs to hardware problems

Encryption failure rarely happens “just like that” - it is usually preceded by one of the following events:

Cause Typical symptoms Device at risk
Interrupted OS update Phone stuck on the logo after reboot, error dm-verity corruption Samsung Galaxy S20+, Xiaomi Mi 11 (when updating to Android 13)
Insufficient memory Message "Insufficient space for encryption" when turning on Devices with 32 GB of memory or less (Redmi 9A, Nokia 2.4)
Power failure during encryption Screen with the inscription «Encryption was interrupted» and a reset offer All devices when the battery is below 15%
Conflict with custom recovery (TWRP) Cyclic reboot after installation firmware Google Pixel 4a, OnePlus 8T (with manual encryption)

The most insidious cases are associated with hardware problems:

  • 💾 Damaged flash memory (especially on cheap smartphones with eMMC 5.1). Symptom: the phone “forgets” the password after a reboot.
  • 🔋 Faulty power controller. Leads to sudden shutdowns during encryption (often on Samsung Exynos).
  • 🛠️ Bad contact after repair. For example, after replacing the charging connector or battery.
📊 Have you encountered errors encryption?
Yes, after updating the OS
Yes, after resetting the settings
Yes, for no apparent reason
No, I haven’t encountered it

How to recognize an encryption failure: symptoms and diagnostics

The first sign of a problem is the phone does not load beyond the logo or the lock screen. However, there are more subtle signals that will help diagnose a failure at an early stage:

🔍 Indirect signs:

  • 📉 A sharp drop in performance after the update (applications take 2-3 times longer to open).
  • 🔄 Spontaneous reboots when connected to a PC or charging.
  • 🚫 Inability to change the password or PIN code in the settings (Settings → Security → Screen lock).

🛑 Obvious errors:

  • «Encryption unsuccessful» - classic failure FDE (requires reset).
  • «Password incorrect» when entering the correct password - a sign of metadata corruption FBE.
  • «dm-verity device corrupted» —partition integrity check error (often after rooting).
💡

If the phone is stuck on the encryption screen, do not hold the power button for more than 10 seconds - this may interrupt the process and aggravate the problem. Try to wait 15–20 minutes: sometimes the system recovers itself after a long pause.

For accurate diagnostics, connect the device to a PC and check the logs via adb:

adb logcat | grep -i "cryptd\|encryption\|dm-verity"

If the logs contain lines like E/cryptd: Failed to decrypt master key or E/DmVerity: Verification failed , this confirms the failure encryption.

Methods of correcting an encryption failure (from simple to complex)

The algorithm of actions depends on the severity of the failure. Let's start with the safest methods that do not lead to data loss.

1. Soft reboot

Suitable for cases when the phone “thought” at the encryption stage, but has not yet generated a critical error.

Hold Power + Volume Down for 10 seconds|Release the buttons when vibrating|Wait for reboot (up to 5 minutes)|Check if the lock screen appears-->

If the PIN code entry screen appears after rebooting, enter it several times in a row (sometimes the system requires re-entering for confirmation).

2. Password reset via Google account (FBE only)

Works on devices with Android 9.0+where it is used File-Based Encryption. After 5 unsuccessful attempts to enter the password, the "Forgot your password?"button will appear. Click it and follow the instructions to reset via the linked Google account.

⚠️ Attention: On devices with Samsung Knox (for example, Galaxy S22 Ultra) this method may block access to Secure Folder even after a successful password reset. Backed up data from this folder cannot be restored.

3. Recovery via Recovery Mode

If a soft reboot does not help, try booting into recovery and resetting the cache:

  1. Turn off the phone (press Power + Volume Up for 15 seconds).
  2. Hold Power + Volume Up until the logo appears recovery.
  3. Select Wipe cache partition (control - volume buttons, selection - power button).
  4. Reboot the device (Reboot system now).

If after this the phone gives an encryption error again, you will have to do a full reset (factory reset). On devices with FBE (Android 7.0+), a reset does not always delete user data - they may remain encrypted, but will not be accessible without the original password.

4. Reflashing via Fastboot (for advanced)

If the reset does not help, you just have to reflash the device manually. To do this you will need:

  • 🖥️ A computer with installed ADB And Fastboot.
  • 📥 Official firmware for your model (download only from the manufacturer’s website!).
  • 🔌 Cable USB Type-C (preferably original).

Instructions for Google Pixel (for other brands the steps may differ):

fastboot flash bootloader [file_name].img

fastboot reboot-bootloader


fastboot flash radio [file_name].img


fastboot flash --slot=all [firmware_name].zip


fastboot reboot

⚠️ Attention: Flashing via fastboot on devices with a locked bootloader (bootloader) will lead to total data loss and may cause hard-brick (irrecoverable failure) Check the status before starting. bootloader command fastboot oem device-info.

What to do if the phone has turned into a “brick”

If after manipulation the device does not turn on at all (no response to buttons, not detected by the PC), this is called «hard brick». In 90% of cases, the reason is damage to the partition boot or recovery during flashing. Solutions:

🔧 Recovery methods:

  • 🔌 EDL mode (Emergency Download Mode) —requires a special cable and software (for example, QFil for Qualcomm or SP Flash Tool for MediaTek). Works even with a damaged bootloader.
  • 🛠️ JTAG programming —connection to test contacts on the board. Expensive (from 5,000 ₽), but restores 95% of the “bricks”.
  • 📦 Replacing the motherboard board is a last resort if the flash memory is damaged (eMMC or UFS).

For devices with Qualcomm Snapdragon (for example, Xiaomi Redmi Note 10 Pro, Sony Xperia 1 III), you can try to recover via 9008 mode:

  1. Disconnect the phone from the PC.
  2. Press Volume up + Volume down and connect USB cable.
  3. In Device Manager the device should appear QHSUSB_BULK or Qualcomm HS-USB QDLoader 9008.
  4. Use QFil or Mi Flash Tool for firmware.
What is JTAG and why is it expensive?

JTAG (Joint Test Action Group) is a standard for debugging and programming chips at the hardware level. To restore a phone via JTAG you need:

1. Special equipment (JTAG box or adapter, cost from 20,000 ₽).

2. Soldering work - connecting to test points on the board (risk of damage due to careless handling).

3. Knowledge of the scheme of a specific model (connection points are different for each phone).

Therefore, services charge from 5,000 to 15,000 rubles for such a service, depending on the complexity.

How to avoid encryption failure: prevention

Preventing the problem is easier than correct its consequences. Follow these rules:

🛡️ Before updating the OS:

  • 🔋 Charge your phone to at least 50% (optimally 80%).
  • 📶 Connect to a stable Wi-Fi network (do not use a mobile data).
  • 📂 Make a backup via adb backup or Google Drive (settings → system → backup).
  • 🔍 Check reviews about the firmware on the forums (for example, 4PDA or XDA-Developers).

🔧 For manual encryption (for example, via TWRP):

  • 📌 Use only official versions TWRP for your model.
  • 🚫 Do not encrypt /dataif you have a custom kernel installed (custom kernel).
  • ⏳ Wait for the process to complete (can take up to 1 hour on weak devices).
💡

On devices with Android 10+, enable the "Automatic recovery" option in the developer settings (Settings → About phone → Build number — tap 7 times, then return to Settings → System → For developers → Auto recovery). This will help the system independently correct minor encryption errors the next time you turn it on.

FAQ: Frequently asked questions about encryption failure

Is it possible to restore data after a reset due to an encryption failure?

On devices with FDE (Android 6.0–7.0), data is permanently deleted On FBE (Android 7.0+) the files remain encrypted, but they cannot be decrypted without the original password. An exception is if you have a backup copy of the encryption keys (for example, via Titanium Backup or Google One).

Why does the phone ask for the old password after resetting?

This is a feature File-Based Encryption. Even after resetting via recovery encryption metadata may be saved. Solution:

  1. Enter the old password (if you remember).
  2. If you don’t remember, do a full flashing via fastboot with formatting userdata.
Is it possible to disable encryption on Android?

On most modern devices (Android 10+), it is impossible to disable encryption without root access. On older versions (Android 5.0–6.0) it was possible to roll back to the unencrypted state via adb:

adb shell sm disable-scrypt

But this only worked on some devices with Qualcomm and often broke the work. applications.

Does flashing to a custom OS (LineageOS, Pixel Experience) help?

Yes, but with reservations:

  • ✅ Custom firmware often bypasses standard encryption bugs (for example, on Xiaomi s MIUI).
  • ⚠️ When installing, you need to format data to F2FS or ext4 (not f2fs on old kernels!).
  • 🚫 On some devices (for example, Samsung Exynos), custom OS may not support FBE, which will lead to new failures.
What to do if the phone is encrypted, but does not accept the correct password?

This is a sign of damage metadata FBE. Try:

  1. Connect the phone to the PC and check the logs via adb logcat for errors. cryptfs.
  2. If there are any in the logs E/cryptfs: Bad magic for real block device -only flashing will help.
  3. On some devices (for example, Google Pixel) you can reset encryption keys via fastboot:
fastboot erase userdata

fastboot erase metadata

⚠️ This will delete all data!