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I have seen Defender fail to detect a virus in a downloaded file once. Things have improved a lot since Windows has added APIs for antimalware products to hook into, but it was an eye opener when Symantec complained improved Windows security was anticompetitive because it broke their dodgy hacks while their competitors products just kept working.
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I like the fact that it does not have much performance impact and does not break things.ģrd party has often broken developer tools, VMware, etc, for me.įor example, a mainstream 3rd party antivirus I tried broke Windows Update inside all my virtual machines a few years back (presumably by man-in-the-middle network traffic filtering leading to Windows Update certificate mismatches).Įven further back, another one broke my Web and database development environment, but their tech support was "we only test our product for ordinary users who just browse the Web and fetch email, not software developers".
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