sethjvm

I had read/heard somewhere that in the past, MS has "invalidated" installs for some pre-release software. I would hate to install this and then have my install "invalidated" so I have to do another install. If you were a betting type of person, what are the chances that MS does this with SP3 RC? Would it be a 50/50 chance that nothing happens or would the chances be higher that nothing happens?