.ESD File Extension
File TypeWindows Electronic Software Download File
This file is saved in a binary format, which requires a specific program to read its contents.
File used by Microsoft's Electronic Software Download (ESD) software, a technology that is used for downloading purchased Microsoft products; saves the downloaded software in an encrypted format (an encrypted .WIM file); used for installing and upgrading purchased software.
ESD files are sometimes seen when upgrading to Windows 7 or Windows 8 using the Microsoft Upgrade Assistant or when purchasing the software through the Microsoft online store.
A common directory to find downloaded ESD files is:
WinPayload.esd - The file downloaded when purchasing and installing Windows 8 using Microsoft's upgrade assistant.