Windows 7 USB/DVD Download Tool is a free tool from Microsoft to easily burn Windows ISO image files to DVD or USB to prepare bootable installation media of Windows 7, Windows 8, and Windows 10.

Although the official Windows 10 Media Creation Tool also enables users to prepare the bootable USB, it can’t create bootable USB by burning an existing ISO image file. In other words, the Media Creation Tool requires you to download a fresh copy of Windows 10 ISO image from Microsoft servers and then select appropriate options to burn ISO file to a USB drive.

While there are plenty of free tools out there to prepare bootable USB to install, most users prefer using the official Windows 7 USB/DVD Download Tool to make Windows bootable installation media.

With default settings, the official Windows 7 USB/DVD Download Tool, like any other bootable USB preparing utility out there, formats the selected USB drive to make the USB drive bootable. The tool even displays the warning before formatting the drive so that users can backup important data from the USB drive to a safe location before formatting the drive.

Make bootable USB without formatting the USB drive

But what if you want to prepare a bootable USB of Windows 10 or previous versions using Windows 7 USB/DVD Download Tool without actually formatting the USB drive? Luckily, it’s possible to force the Windows 7 USB/DVD Download Tool to prepare the bootable USB without formatting the drive. All you need to do is make a small change to the Registry.

NOTE: You can also use the popular EasyBCD tool (free for personal use) to prepare the bootable USB without formatting the USB drive.

Complete the given below directions to configure Windows USB/DVD Download Tool to prepare bootable USB of Windows 10/8/7 without formatting the USB drive.

If you’re new to Registry, we recommend you create a system restore point or system image backup before proceeding further.

Step 1: Open the Registry Editor. To do so, type Regedit in the Start menu search box, and then press Enter key. Click Yes button when you see the User Account Control dialog.

If the Start menu search is not working, simultaneously press Windows and R keys to open Run command dialog, type Regedit in the field, and then press Enter key to open Registry Editor.

Step 2: In the Registry Editor, navigate to the following key:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\ISO Backup Tool

Step 3: Select the ISO Backup Tool key, on the right side, create a new DWORD (32-bit) Value by right-clicking on the empty space, clicking New, and then clicking DWORD (32-bit) Value and finally, name it as DisableFormat.

Step 4: Double-click on the newly created DisableFormat value and change its value data to 1 (one) to stop Windows 7 USB/DVD Download Tool from formatting your USB drive while preparing the bootable USB of Windows 10/8/7.

To restore original settings, delete the DisableFormat value.