The device is not ready: How to fix this PC error

Madalina Dinita
by Madalina Dinita
Managing Editor
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The device is not ready

If you’re getting the ‘ERROR_NOT_READY’ error code with ‘The device is not ready‘ description, follow the troubleshooting steps listed in this article to fix it.


The ‘ERROR_NOT_READY’ error code, also known as error 0x80070015, usually occurs when users try to save data on their drive, and particularly when they want to back up their files and folders. Error 0x80070015 affects all Windows versions.

Microsoft explains that there are three main causes that trigger ‘The device is not ready’ error: the drive is empty, the drive is already in use, or there is serious hardware failure due to corrupted or incompatible USB controllers device drivers.

There are also cases when ‘The device is not ready’ error also appears when users try to start programs checked by UAC.

How to fix error 0x80070015 ‘The device is not ready’

Solution 1 — Check the drive connection

This error often occurs on external drives, so make sure that the device is properly connected to your computer. You can also unplug it and plug it back in to establish the connection. You may also want to temporarily disconnect unnecessary peripherals and plug them back in after you’ve regained access to your drive.

Solution 2 — Close the programs using the drive

‘The device is not ready’ error may also occur if active programs are using the drive. As a result, close all the apps and programs using the drive and then retry the command to see if that fixed the problem.

Solution 3 — Run the Hardware and Devices Troubleshooter

Windows comes with its own built-in hardware troubleshooter that can fix general issues causing your hardware to malfunction.

Here’s how to use this feature on Windows 10:

  1. Go to Start > type ‘settings’ > double-click the first result to launch the page
  2. Go to Update & Security > select Troubleshoot in the left-hand pane > select Hardware and Device > Run the troubleshooter

To use the built-in hardware troubleshooter on older Windows versions, follow these steps:

  1. Go to Start > type ‘control panel’ > double-click the first result to launch Control Panel
  2. Go to Hardware & Sound > View devices and printers > right-click the problematic drive > click Troubleshoot in the drop down menu
  3. Wait for the troubleshooting to complete > retry your computer to check if your drive is now available.

It is worth mentioning that some external drive manufacturers offer their own dedicated troubleshooters. If ‘The device is not ready’ error still persists, go to your drive manufacturer’s website and check to see if there is any drive troubleshooter available. If this is the case, download and install the troubleshooter and run it to fix your drive.

Solution 4 — Uninstall and reinstall the USB controller  driver

  1.  Press the  Windows key + X > select Device Manager.
  2. Locate and expand “Universal Serial Bus controllers” in the Device Manager window.
  3. Right-click the “Universal Serial Bus controllers” >click on “Uninstall”. You can also uninstall the drivers individually.
  4. Restart your computer and check this action solved the problem.

Solution 5 — Assign a drive letter to your external drive

  1. Press Windows Key + R to bring up the Run window > type diskmgmt.msc to bring up the disk management console.
  2. Right-click on the external drive to open the Drive menu.
  3. Click “Change Drive Letters and Paths” > click the “Change” button
  4. Click the “Assign the Following Drive Letter” radio button > select the drop-down box to view the available drive letters
  5. Select the desired drive letter to assign to the external drive > click “OK.” A warning message will appear > click OK.

Solution 6 — Install the latest latest drivers in  compatibility mode

Install the latest driver for USB from your drive’s manufacturer website, and try installing it in Windows 8 compatibility mode to run the program using settings from a previous Windows version.

  1. Download the driver from the manufacturer’s website.
  2. Right-click on the driver setup file > select Properties
  3.  Click on the Compatibility tab > check the box “Run this program in compatibility mode for” and select Windows 8 from the drop down menu.
  4. Once the installation completes, restart your computer and retry your command.

Solution 7 — Run a full system scan

Malware may cause various issues on your computer, including errors. Perform a full system scan in order to detect any malware running on your computer. You can use Windows’ built-in antivirus, Windows Defender, or third-party antivirus solutions.

Here’s how to run a full system scan on Windows 10 Creators Update:

  1. Go to Start > type ‘defender’ > double click Windows Defender to launch the tool
  2. In the left hand pane, select the shield icon
  3. In the new window, click the Advanced scan option
  4. Check the full scan option to launch a full system malware scan.

Solution 8 — Repair your registry

The simplest way to repair your registry is to use a dedicated tool, such as CCleaner. Don’t forget to first backup your registry in case anything goes wrong. If you haven’t installed any registry cleaner on your computer, check out our article on the best registry cleaners to use on PC.

You can also use Microsoft’s System File Checker to check for system file corruption. However, this utility is only available on Windows 10. Here’s how to run an SFC scan:

1. Go to Start > type cmd > right-click Command Prompt > select Run as Administrator

2. Now type the sfc /scannow command

3. Wait for the scanning process to complete and then restart your computer. All corrupted files will be replaced on reboot.

Solution 9 — Update your OS

Make sure that you’re running the latest Windows OS updates on your machine. As a quick reminder, Microsoft constantly rolls out Windows updates in order to improve the system’s stability and fix various issues.

To access the Windows Update section, you can simply type “update” in the search box. This method works on all Windows versions. Then go to Windows Update, check for updates and install the available updates.

Solution 10— Clean boot your computer

A clean boot starts Windows by using a minimal set of drivers and startup programs to eliminate software conflicts that may occur when you install a program or an update or when you simply launch a program.

Here’s how to clean boot your Windows 10 computer:

  1. Type System Configuration in the search box > hit Enter
  2. On the Services tab >  select the Hide all Microsoft services check box > click Disable all.

hide all microsoft services windows 10

3. On the Startup tab > click on Open Task Manager.

4. On the Startup tab in Task Manager > select all items > click Disable.

disable start up items windows 10

5. Close the Task Manager.

6. On the Startup tab of the System Configuration dialog box >click OK > restart your computer.

Check if ‘The device is not ready’ error still persists.

Here’s how to clean boot your Windows 7 PC:

  1. Go to Start > type msconfig > hit ENTER.
  2. Go to the General tab > click Selective Startup.
  3. Clear the Load Startup items check box.
  4. Go to the Services tab > select the Hide All Microsoft Services check box > click Disable all > hit OK.
  5. Restart the computer when prompted > check if the issue still persists.

Solution  11 — Check your disk for errors

On Windows 10, you can run a disk check using Command Prompt.

Start Command Prompt as administrator and type the chkdsk C: /f command followed by Enter. Replace C with the letter of your hard drive partition.

As a quick reminder, if you do not use the /f parameter, chkdsk displays a message that the file needs to be fixed, but it does not fix any errors. The chkdsk D: /f command detects and repairs logical issues affecting your drive. To repair physical issues, run the /r parameter as well.

On Windows 7, go to hard drives > right-click the drive that you want to check  > select Properties > Tool. Under the ‘Error checking’ section, click Check.

There you go, we hope that at least one of these solutions helped you fix ‘The device is not ready’ error code. As always, if you’ve come across other solutions to fix this problem, you can help the Windows community by listing the troubleshooting steps in the comments below.