Hi.
So, I noticed after the Christmas holiday that I suddenly started getting an error when I clicked “Play” on the launcher to start the game. Sometimes this would result in a BSOD/reboot, and other times it would just crash the game. The text of the error was something about “Fatal disk-error (1450) on read” and related to the file GW2.dat in the Guild Wars 2 directory. This file is 15GB in size.
I tried running chkdisk, defragmenting my hard drive, and several other things I saw suggested. The only thing that kind of worked was starting the launcher with the “-image” option to re-download everything. That fixed it for one play session, but then it promptly started crashing again the next day.
Then I noticed on some web page somewhere that someone said the GW2.dat file is a compressed file. I recalled that I had, over the holiday, purchased some new, large games via Steam and installed them. Because of this, my available HD space was down to about 30GB or so. The crashing had started around that time.
I deleted many old games I hadn’t played for months and was able to increase my free HD space to around 70GB, and since then I haven’t had GW2 crash at all. My theory is that somehow the GW2.dat file is uncompressed when the game is started, or perhaps the game calculates how much space it would need to decompress the file, and finds there is not enough free space and crashes.
Anyway, I spent a lot of time Googling for a solution to this and didn’t find one, so I thought I’d post what worked for me.