What with a now heavily modified FSX, I'm starting to run out of space on one partition of my hard drive. However, there is extra space on the other partition, and I figured it'd be easier to make a straight copy of the entire FSX folder and shift it across to the other drive, rather than reinstall it and try to install all my addons again.
Now I've done this before with FS9, so I assume it's possible, but from there on, the game is still recognised by its registry entry as being on the drive you moved it from. If you don't attempt to modify it, anyway.
I've tried to manually alter the registry through regedit before, but I'm still unsure of a way to completely change it so the sim 'thinks' it's sitting in the right place! I managed it with FS9, but I seem to remember an installer doing it automatically for me, when I tried to install something to the new location.