First you will need to download this. It is the command line tool you will be using.
1. Put your install.esd in C: (your C drive)
2. Extract ESD2WIM-WIM2ESD-v2.zip by double clicking on it and extracting it to the same location.(It does not matter where this is placed.)
3. Go into ESD2WIM-WIM2ESD-v2 folder and right click on ESD2WIM-WIM2ESD and run as administrator.
4. The command prompt will ask you to enter the location of where the install.esd file is. It should be C:install.esd.
At the top it should show Detected ESD File contains x indexes (x being the number of indexes)
The first index should work. In my case there was only one index so we will use that one.
5.Type: 1 and it will start to convert and export the install.wim. You do not need to press enter once you type 1 it will start the conversion.
Once that is done you should see the completed install.wim in the ESD2WIM-WIM2ESD-v2 folder.