I can confirm this works, I had the exact same problem and running on Win7 with a nvidia-card and doing this solved it for me! If windows doesnt allow you to delete the folder you can just reboot in safe-mode and do it that way!
Getting same problem win7 x64 RADEON video except it lets me log the bot in, but as soon as i hit start wow+bot close instantly
its brand new laptop, so i just went and updated ALL drivers to latest, fresh HB, still no luck as soon as i click start (Botbase GB2 plugin Rare killer.) instant close. no crash logs generated, if i force Wow to crash using outdated hacks of the net, crash reports are generated just nor for this crash.
LOLOLOLOLOLOLOLOL please excuse my failing 0.o it was not crashing Activity Hearth and exit, bags were full :S /shame