
218 4.4 Scale out and scale up
4.4.2 The difference between service packs, hotfixes,
and QFEs
The basic difference between these updates lies in the fact that Service Packs
have undergone regression testing, both within Microsoft’s testing labs, and
at sites of customers participating in beta programs. Hotfixes and QFEs, on
the other hand, are one-shot fixes, tested to fix the customer problem, but
they have not undergone any regression testing. Security hotfixes are man-
datory updates from Microsoft and you are generally asked to deploy these
fixes as they are officially made available. Don’t take a chance here, and of
course, because security hotfixes tend ...