What’s a Service Pack?

Reader D writes:

Hi Woody, Thanks for all your help.

I have upgraded to Firefox 3.0.10.

I give up, I thought I knew what Windows Service Pack is, but I guess I don’t.

I don’t think I ever loaded any update with Service Pack in it. Vista is running fine.

I have KB955430 as an update in waiting. I checked out the “details” online and found a page saying that some PC have trouble rebooting after the update, instructions on removing it, nothing positive…

What exactly is a Service Pack ?

A Service Pack is  a big rollup of patches, sometimes including new features, that Microsoft releases from time to time. Some Service Packs are relatively minor. Others are tantamount to an entirely new release of the product.

KB 955430 is [a prerequisite for*] Vista Service Pack 2. For now, I recommend that you hold off on installing it – for precisely the reason you mention, people are reporting some problems. That’s expectable with a Service Pack. Microsoft is “pushing” it through Automatic Updates and, like most changes pushed through Automatic Updates, there’s no reason to run out and blithely install what Microsoft says you should install. Far better to wait and see what problems develop.

Watch the MS-DEFCON level.

[* Thanks to JP for pointing out that this KB article is NOT the Service Pack. It's a prerequisite for Vista SP2, which isn't out yet.]