Unlike previous Windows 10 Technical Preview builds, the latest public build, Windows 10 build 10049, is taking a significantly longer time to install on some users. Πολλοί από τους testers του προletterof Windows Insiders they noticed the slow time informations but also the fact that the new functional needed extra space on their hard drive. Below we will see together how you can free up 2.5 GB of disk space after installing Windows 10 build 10049.
The problem starts with language packs that come with updating Windows 10 build 10049. Because the packages are quite a lot (Greek still not included btw) so it takes more time to install. This particular problem only occurs to those who have upgraded their system through Windows Update.
Οι χρήστες που πραγματοποίησαν ένα clean install from ISO of Windows 10 build 10049 were not affected.
Apparently the error is due to updates of Microsoft, who made all language packs available during the upgrade from build 10041 to build 10049.
To test whether you are affected by this issue, and to release up to 2.5 GB from the drive that Windows is installed, follow the instructions:
Press the keys together Win + R to display the RUN window and type the command:
lpksetup / u
Wait a few seconds until the window for “Install or Uninstall languageappearance”:
Select the languages that do not useste and proceed to remove them. If you leave only the English language, and so you will free up around 2.5 GB of disk space.
If your lpksetup window resembles the one shown in the figure below, this means you do not have additional languages on your system. 
Please note that the above instructions can also be used to remove language packs in Windows 8, 8.1, and 7.
