You can follow these troubleshooting steps to fix the cannot read error that pops up when you try to manually sideload an OTA update with ADB.
I write about a lot of tips and guides here on Android Explained, and I do so in a way that hopefully makes it easy to follow. I break things down into step by step instructions as I walk you through the entire process. I saw a demand for companion videos for each of these articles, so I started to do that earlier this year as well.
This reinforces the notion of walking you through the step by step instructions to make it as easy to follow as possible.
Still, no matter how much effort I put into this, there are always going to be instances where something doesn’t work out correctly. I can point to my video and show you proof that it worked for me, but that doesn’t help anyone else if they come across an issue that I didn’t have. I try to answer questions in the comments to the best of my ability, and even go as far as to spend time researching solutions via Google.
Recently I saw some people asking how to resolve a “cannot read” error they were getting when trying to sideload an OTA update. I had not come across this so I wasn’t aware of how to fix it, but that changed yesterday. I had tried to sideload the Android 7.1.1 OTA update on my Nexus 6P, and got this cannot read error. So after doing some research, I want to present you with some troubleshooting steps to take if you ever come across this issue.
Double Check Things
Before getting into the step by step process that shows what I did to fix the cannot read error when I was trying to sideload an OTA update, you should be sure you’re double checking all of the required steps. For instance, you need to make sure that the update ZIP file has been moved or copied into the exact same folder that your ADB and Fastboot tools are located. This is different for each person, as people install these tools into different directories.
The next thing you should try is downloading the update ZIP file again. Sometimes this ZIP file can become corrupt when you download it or when you copy/move it into the same directory that your ADB and Fastboot tools are located. I understand that it can be a hassle to do this if your internet connection is slow, but it’s something you should be checking before you start to tinker with the drivers.
After I did both of these checks, I then resorted to uninstalling the USB driver for my Android device, even though I never had any issue with the driver in the past. I can’t emphasize this enough. I almost skipped this troubleshooting step because I assumed my drivers were okay since I do tons of these mods with dozens of devices and have never had any issues.
Fix Cannot Read Error
- Enable Developer Mode on the phone
- Enable USB Debugging Mode on the phone
- Double click on the Minimal ADB & Fastboot tools shortcut
- Type in the following command. . .
- adb devices
- . . .and press Enter on the keyboard
- Connect the phone to the PC with a USB cable
- Grant USB Debugging access from the PC to the phone
- Open up Device Manager on the Windows PC
- Expand the ‘Android Device’ option
- Right click on the device listed in the ‘Android Device’ option
- Click on the ‘Properties’ option
- Click on the ‘Drivers’ tab
- Click on the ‘Uninstall’ button at the bottom
- Click the check box to delete the software
- Then click on the OK button to confirm you want to uninstall the USB drivers
- Reboot the PC
- Let Windows install the USB drivers again once it boots back up
- Try to sideload the OTA update with ADB again
Now, I just want to preface this by saying what worked for me might not work for you. I can only say this is what helped to fix the issue I was having, and hope that it is helpful to others as well. I was going to manually reinstall the USB drivers after the PC booted back up, but decided to try the ADB sideload command after I saw Windows had already installed some on its own. This could be different for another version of Windows, so you might need to manually install those USB drivers afterwards.
As mentioned, you will need to enable Developer Mode on your phone so that you can turn on USB Debugging Mode. This is required in order for the phone to show up in Device Manager under the Android Device label. I always instruct people to install Minimal ADB & Fastboot tools, as it small, easy to install, and comes with a convenient desktop shortcut. If you don’t use this, you’ll need to launch the Command Prompt on its own and manually navigate to where you have ADB & Fastboot tools.
We need to start the ADB service so that the device is recognized by Windows with USB Debugging Mode enabled (at least this is what I did). You can then connect the phone to the PC with a USB cable, and grant USB Debugging access from the PC if you haven’t done so in the past. From here, you can then open up the Device Manager from the start menu, or control panel or however you like to open Window’s Device Manager.
You should see an option here labeled Android Device, and that should be able to be expanded to reveal a device under this label. You want to right click that device (under the Android Device label) and then click on Properties. This will take you to a page where you see a number of tabs across the top. Click on the Drivers tab, and then click the Uninstall button that you see toward the bottom.
You’ll be asked if you are sure you want to uninstall the drivers. There should be a check box that asks if you want to delete the driver software for this device (at least I get this option on Windows 10). I checked this box, clicked the OK button and then told Windows to reboot now when I was prompted to. I waited for the computer to boot back up and then noticed Windows has already installed new USB drivers for the phone (since I had kept it connected to the PC).
To test things out (before manually installing any drivers), I opened up the Command Prompt again and tried the ADB Sideload command and it instantly started to load the OTA update ZIP file. If it doesn’t for you, or if Windows doesn’t install the USB drivers for you automatically, you probably want to look into manually downloading them from Google.