UAC is not a security feature/ boundary (even according to MSFT themselves). It was aimed to help stop ISVs from writing software assuming admin privileges. Vi

UAC is not a security feature/ boundary (even according to MSFT themselves). It was aimed to help stop ISVs from writing software assuming admin privileges. Vista had A LOT of security improvements overall, but UAC shouldn't be considered as one of them (similar to PatchGuard for x64 Windows - it's cited as sometimes a security feature, but it's not).