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Unlike Windows Vista installation discs, which permitted the choice of install (this was only if you did not input your key during install AKA activate later) Windows 7 does not give you the opportunity to choose your edition. However the install.wim file does contain all variants and this can be overridden by modifying the “EI.CFG” file on the DVD contained within the sources directory.

The file contents looks like this:

[EditionID]
Ultimate
[Channel]
Retail
[VL]
0

Personally I would have preferred that Microsoft allow us to choose, but I’m sure they had their reasons to not adopt this approach.

Credit – Aidan Finn