Use a lightweight, portable scanning application (such as NAPS2 - Not Another PDF Scanner 2) on your USB drive.
When prompted to choose your printer driver from a list of manufacturers, click the button in the lower right corner.
The term "portable" usually describes software that doesn't require a traditional installation process. For a printer driver, "portable" is something of a misnomer, as most modern printer drivers do need to be installed. However, users searching for this keyword are usually looking for:
If you had an older Toshiba model, use the "Printer Management" tool to remove old drivers entirely.
Click , navigate to your portable USB folder, select the primary setup file (usually EST2303.inf or similar), and click Open.
Download official drivers: