Help I accidentally downloaded the "Windows 10 Download tool" (i'm running 8.1) onto my 2 terrabyte usb drive thinking it would create a small folder file / partition and instead it looks like it has formatted the drive and is using 3.9GB on a formatted 39.9 GB partition. I cannot see the rest of the disc which has important work and personal backups on it. Recuva only sees the "new" formatted partitions
just to clarify, you downloaded the Win10 Download tool aka the Media Creation Tool, which is only 20MBs or so.
did you than run said tool and it has created the 4GB partition?