To install a default instance, run the following command. Square brackets [ ] enclose optional attributes and angle brackets <> enclose parameters values.
msiexec /i <full_path_to_msi> [INSTALLDIR=<Web_Root_directory_path>] [ENABLE_WEB_SUBDIR=1 WEB_SUBDIR=<Web_Root_directory_path>]
Values containing spaces must be enclosed in quotation marks ("). For example:
INSTALLDIR="C:\Program Files\wwwroot"
Example:
msiexec /i C:\temp\Web-to-HostSetup.msi INSTALLDIR=C:\inetpub\wwwroot ENABLE_WEB_SUBDIR=1 WEB_SUBDIR=w2hServer