Add a language pack these days can be done in different ways, I recommend do it by DISM. Here´s a guide how you can do it
What you need
* Powershell 3.0 or later.
* Windows 10 Pro 1703 or later
Ok, Now we need to put some files on the right place to begin, Start to create a folder structure like this.
1. Start with ISO folder.
1.1 Download the ISO from Voluming Licensing Service Center or a Windows 10 EVAL ( https://www.microsoft.com/en-us/evalcenter/evaluate-windows-10-enterprise)
1.2 Just right click on the ISO and Mount
1.3 Copy all the files from the Mounted ISO to your ISO folder.
1.4 Now it gonna look like this.
2.1 Download the CAB file here: https://www.itechtics.com/windows-10-version-1709-language-packs-direct-download-links/#Swedish
2.2 Copy the CAB file the the “Language_files” folder.
2.3 Now its gonna look like this.
3. Scratch its just a empty folder.
4. temp_ISO also is a emtpy folder
5. Lets start the scripting. Open up the Powershell script.
You can find it Here:Add-Language-pack
6. Open up the script and we need to do some Editing.
7. Edit the variables so it fits your environment.
8. Run your variables
9. Now in Windows 10 1709 its same ISO for PRO, PRO N, Enterprise, Enterprise N etc. So we need to figure out what Index we want to modify
10. In my case, I want to modify Windows 10 Enterprise N, Run the variable
11. Now its time for some Action, Run the next line, to “#Mount your ISO with that specific index and put it in a temporary folder.”
11. Then run the next one, #Time to Add the language pack
12. Time to run the next one. “#Do changes in the mounted Image”
13. Ok, Now the last command, #Unmounting the ISO file and saving it..
14. The language pack is now into the .ISO file, and you have succeeded to do your mission.
15. We need to modify the answer file, if you want to deploy this with MDT/SCCM, otherwise, it will choose EN because its “standard” on the ISO file
16. Open Windows System Image Editor on your machine ( you need ADK to have this program installed)
17. Right click on Select a Windows image or catalog files – Select Windows Image..
18. Choose the .ISO file that you just modified.
19. Choose the Index that you wanna modify, In My case Windows 10 Enterprise N
20. Rightclick “Create or open an answer file” then New Answer file.
21. Click on Components then “amd64_Windows-International-Core_10.0.16299.15_neutral then Add Settings to Pass 4 specialize
21. Change Settings like below
22. Click on Components then “amd64_Windows-International-Core_10.0.16299.15_neutral then Add Settings to Pass 7 OOBesystem
22. Change Settings like below
23. Save the file and name it like answer.xml or something like that.
24. Now we are done, You have a proper ISO to work with, and a answer file that will change the language while deploying your machines.