Problem launching the client.

[Vaha75]

I was playing and enjoying the game up until yesterday evening—except for the issues with attacks. But then I got the bright idea to update the client; I hadn't updated it in ages. Since I'm on Windows 7, I have to run the update via a virtual machine running Windows 10. But here's the problem: the launcher deleted `Wow.exe` and then said, "Oops, I can't update." I re-downloaded the client via the launcher, launched it, and—bam—an error! I downloaded the client via torrent and the archive, but for some reason, I'm still getting an error.
I would greatly appreciate your help; thank you in advance.