If the physical buttons or SD card method fail, try official software recovery tools. Install Huawei HiSuite on your PC.
The tablet should enter "Automatic Update" mode and begin verifying the authorized image. 2. Alternative: Huawei eRecovery & HiSuite
If you are intentionally repacking the recovery image for development purposes: How to Fix Huawei Recovery Image Verify Failed Error huawei s7721u recovery image verify failed repack
The most reliable way to bypass this error is to return the device to its factory-authorized state.
Use a reliable MicroSD card formatted to FAT32 . If the physical buttons or SD card method
Select in HiSuite and follow the prompts to download authorized images.
Connect the device to a charger and hold Volume Up for ~15 seconds to enter eRecovery. Select Download latest version and recovery to let the device fetch official firmware over Wi-Fi. 3. For Advanced Users: Repacking Correctly Select in HiSuite and follow the prompts to
Encountering the message on your Huawei MediaPad 7 Youth (S7-721u) typically signals a signature mismatch. This occurs when the device's bootloader—which is likely locked —detects a recovery image that has been modified, incorrectly repacked, or is not digitally signed by Huawei. Understanding the Error