I had to remove 6.3 from my Windows XP 64 bit system, screwed up my toolbars, 100% cpu usage and visual studio crashes.
From 2 replies above the one you have posted, by Neil Banfield, WB Dev.
We do not support 64 bit XP as an OS I am afraid, but we are seeing if we can make it install 6.2 files on XP 64 instead.