If I wanted to reload SBS ....

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My searches for reloading SBS have been essentially fruitless. I have found
some info on moving to a new server, but not on a method for reloading SBS on
the same platform and recovering my environment (AD, Exchange, etc).

Succinctly, my question is: Is there a documented/supported method to reload
SBS in a production environment and recover my existing site-specific
information?

I have *numerous* problems with the exisiting load, to the point that
attempting to fix each item has *got* to be longer than starting again.

Can SBS be simply reloaded/repaired right over the top of the existing
installation (and not lose the AD and Exchange data)?

TIA!
.