(edited by Medieval.1679)
Returning to game - download issues
If you have a friend with the game within travel distance, you can copy the game files from them and plonk them directly into your game folder. The dat file is what you want… It’s the only 20+ gb file there so you can’t miss it
The progress on the launcher is based on the files remaining to download, rather than what you’ve downloaded compared to the total. Because of this, your progress will always start at 0%. Thinking it’s starting over is a common mistake. For comparison, a fresh install is around 300k files.
If you’re sure it’s installing all over again however, ensure that you’re running Gw2.exe rather than Gw2Setup.exe. Also ensure that Gw2.exe was installed to the location of your choosing. If you ran Gw2Setup.exe and were never asked where to install it, it would have selected your %temp% folder by default, which is not a safe spot. You can search that folder for Gw2.dat to try to recover it, but it would have been overwritten when you ran Gw2Setup.exe again. Instead of running Gw2Setup.exe, rename it to Gw2.exe and place it wherever you’d like, such as C:\Games\Guild Wars 2\Gw2.exe.