First make sure you're looking in the correct place. The caching may be happening in windows itself or your application software rather than IIS. But it's possible IIS caches group membership the first time it's accessed, but I don't know myself, sorry. In the old days of classic asp you could do a quick edit on global.asa and that would force a reset of application variables. I doubt that helps you though
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Doug G
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I've never been able to appreciate the sublime arrogance of folks who feel they were put on earth just to save other folks from themselves .." - Donald Hamilton