So frustrating...I am also having the same issue. Recently got a new computer and upgraded to Windows 10, and am unable to download the game past a certain point. I didn't check the exact % where the initial download stopped, but I am only able to load all the core and HoT maps. Going into the PoF and LS4 maps is like sending my character into a black hole: the map never loads and my character is trapped in limbo lol (even logging out and logging in can't retrieve them from the non-loading map). Ever since the initial download (which was very smooth), my installer will show that it downloads up to 5 GB, but the actual .dat file doesn't change in size and the "number of files remaining" doesn't change, so I guess I'm just wasting bandwidth. The download speeds then drops to 0 and stays there. The only way to get any progress is to close and re-open the launcher, which seems to allow it to download another ~4 - 6 files, before it stops downloading (even though the installer says it's continuing to download, into the GB range). I then have to close and restart the installer to download the next 4 - 6 files. The "language switch" trick probably is just doing this -- forcing the installer to restart every time you switch languages. Is this a recent problem, or just a Windows 10 problem? I was able to download the entire .dat file in a single shot back on Windows 7, even if the download took me days. Now, running the installer for days doesn't achieve any more progress than if I run it for a few seconds and close/restart the installer.