>I am trying to decide if I should install Service Pack 3. If I do install it on my system, does it mean that I must also send an update of the runtime version to all of my customers? Can I install Service Pack 3 on my machine and continue sending program updates to my customers who have Service Pack 2 runtime?
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As long as you don't use any of the extensions added to SP3, your executables would be compatible, but I'd think it to be far more critical to update the target systems, since the runtime in SP3 is significantly more stable than the initial Runtime release. I sent out updates to the SP3 runtime before ever recompiling a line of code; many of the probelms addressed in SP3 were quite troublesome, and performance of many commands, such as indexing operations, were improved in SP3 as well.