MDAC distribution in the real world
If you look at MSDN, you can find docs that list all the various installs that included various versions of MDAC (like 2.1 is in IE5 and 2.5 is in Win2K, etc.). What I'd really like to know though, is what percentage of various versions you can find in the wild. Something like google's zeitgeist would be great.
The surest way is to look which version of MDAC comes with each OS version. Windows 98 SE is the first that has a reasonable version of MDAC: 2.1. I've seen quite a few companies that specify Windows 98 SE as the minimum version, although I'm not sure that's wise. My own software will work on Windows 98, too; if the installer finds that MDAC 2.x isn't installed yet it will download and install it.
I can probably use 2.1. I haven't tried yet. I just need to get my hands on a clean box. So far, the ones I've tried already had 2.5 or later.
Looking at DLL Help (hell?) database tells you what version of certain files shipped with what.
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