Case :
You’ve previously installed Office 2013 (your sysprep reference image) and are now ready to install an additional language pack. To make the installation silent, you’ve made an unattended XML answer file. You launch the installation with Setup.exe /config Config.xml but the installation halts with an error message :
Yes, this is not an English message, remember that we are installing language pack and stupidly enough, the installer prefers displaying error message in the package language rather than in the OS one… Anyway, you can read it in plain English if you dive into the log file, and the message is : Error: The preferred product was not found in the available products of the SKU. Type: 41
(It may also help : you won’t be able to see this message if you’ve not set the option SuppressModal="yes" in your config.xml File)
Why :
A review of the log file clearly shows that installer identiifed, not only one, but three different products :
The main reason for this is that language pack are distributed with localisation for all Office products while Office 2013, Project and Visio are three distinctive SKU downloadable separately.
Solution :
Easy to fix : go to your language pack folder and suppress folders Project.fr-fr et Visio.fr-fr (fr-fr is just for my example, replace this with the language pack you work with). Relaunch the intaller. All should work smoothly now !