I can imagine the inconvenience you have experienced.
Here are a few methods which you can follow to resolve the issue:
Temporarily disable any third party security program (if installed) and take a look at to install the language pack.
Important: Antivirus code will facilitate shield your laptop against viruses and different security threats. In most cases, you should not disable your antivirus software. If you have got to quickly disable it to put in different code, you ought to re-enable it as presently as you are done. If you are connected to the net or a network whereas your antivirus code is disabled, your laptop is prone to attacks.
Step 2 :
Download and install the language packs manually in Clean Boot mode and check.
A clean boot helps to eliminate code conflicts and to see what's inflicting the matter. Perform a clean boot on the pc by following the steps given within the link:
Note: Applies for Windows eight.1 also.
Important: when you've got finished troubleshooting, check with the article "How to reset the pc to begin as was common when troubleshooting with clean boot" for Windows eight, given beneath the section "More Information" to reset the pc to begin as was common from the on top of link.
Also refer:Add a language or keyboard
Hope this helps. If you have any further queries/issues related to Windows, write to us and we will be glad to assist you further.