Remove all USB thumb drives, SD cards, and external HDDs.
Before booting from your USB, physically disconnect the SATA or power cables from your secondary hard drives. If they aren't connected, the installer cannot touch them.
If you use the "Reset this PC" feature within Windows settings rather than a USB boot drive, you may see an option to "Clean all drives." If you toggle this on, Windows will wipe every connected disk. does clean install wipe all drives exclusive
By default, a clean installation of Windows or macOS is designed to target the (usually your C: drive). It does not automatically reach out and "sanitize" your secondary D: drive, external backup disks, or secondary SSDs unless you manually intervene during the partition process. How a Clean Install Works
Sometimes, users realize their files were only on the desktop (C: drive), which is wiped. Even if the secondary drives are safe, your primary user profile data is gone. How to Ensure "Exclusive" Wiping Remove all USB thumb drives, SD cards, and external HDDs
Once you are back at the desktop, shut down and plug your drives back in. Windows will recognize them immediately, and your files will be right where you left them.
The short answer is , but with a very important "it depends" regarding how you configure the setup. The Short Answer: It Only Wipes What You Tell It To If you use the "Reset this PC" feature
A clean install is It is not a global command that nukes every bit of storage connected to your motherboard. However, because the interface can be confusing, the safest bet is to unplug your data drives before you begin.
This is where your OS lives. To do a "clean" install, you typically delete the partitions on this drive, turning it into "Unallocated Space." This wipes the data on that specific drive .