Home > Tips and Tricks > Android

fastboot flash recovery_ab not working: How to Fix

In this guide, we will show you a couple of methods to fix the fastboot flash recovery_ab not working error. The flashing process has never been the same ever since the introduction of A/B partitions. Moreover, the entire scenario of these active and inactive slots only makes the matter worse, especially for those who are just setting their feet in the custom development.

For instance, if you are flashing a file to both the slots, then you might have come across a command that has the _ab suffix at the end. For example, if you want to flash a custom recovery to both slots, you could do so via the fastboot flash recovery_ab command. However, that doesn’t seem to be working for some.

While the CMD window could send the file to the device, but the device is unable to write it and instead ends up giving out the following error message: Failed remote: ‘(recovery ab_b) No Such Partition’ error [in place of ‘b’, you might also get ‘a’, depending on the current active slot]. If you are also facing this issue, then this guide will make you aware of a couple of nifty workarounds that should help you rectify this bug. Follow along.

Fix fastboot flash recovery_ab not working

fastboot flash recovery_ab

Before starting, please take a backup of the stock recovery from the firmware that is currently installed on your device. This is because if something goes wrong, then you could easily flash the stock recovery and fix that issue. Droidwin and its members wouldn’t be held responsible in case of a thermonuclear war, your alarm doesn’t wake you up, or if anything happens to your device and data by performing the below steps.

FIX 1: Update ADB

The older versions of ADB don’t support the _ab command flashing. So please update it to the latest build and then check if you are able to execute the command.

FIX 2: Use –slot=all

Instead of using the _ab suffix,m you could use its –slot=all counterpart. For example, in place of fastboot flash recovery_ab twrp.img, you should use fastboot flash –slot=all recovery twrp.img

FIX 3: Manually Specify Slots

Rather than combining both the slots in one command, you should them down into two separate commands and then retry flashing. So instead of fastboot flash recovery_ab, you should use fastboot flash recovery_a and fastboot flash recovery_b and then check if it rectifies the issue.

FIX 4: Don’t Specify Slots!

While it might sound counterintuitive when compared with our other fixes, but in some cases, there is no need to manually specify the slot. Just use the partition name and you are good to go. For instance, in our case, instead of fastboot flash recovery_ab, you should use the fastboot flash recovery command and check out the results.

That’s it. These were the four different methods that should help you fix the fastboot flash recovery_ab not working error. If you have any queries concerning the aforementioned steps, do let us know in the comments. We will get back to you with a solution at the earliest.