Re: Admission
There is one aspect of old AV software that is worth remembering. It has complete access to the entire system, and it can itself become a vector for infection. We have already seen this, where the AV software's update mechanism could be turned against it and used to install malware.
Let me see, which one was it that had that problem. Ah yes, MS defender!
It would be highly weird if MS used that particular example as part of their defence against Kasperky's case...
That doesn't mean the point is invalid. Old AV software can be very dangerous if exploitable bugs are found. If so, removing it is likely better than leaving it running. But MS declaring it to be actually dangerous simply because it old is probably a step too far.
What seems totally indefensible is MS managing what apps install or not based on some weird perception of compatibility. An application is either compiled for Windows, or it's not. MS's criteria seem to be covering other aspects of applications (colour scheme?).
I could understand it a tiny bit if an application was using a deprecated API call. If that's the case then they should put up a dialogue box saying so, or just complete the deprecation process by actually removing the API call from the OS. That would break the application, but at least there'd be a trail of notices to developers giving fair warning.
I'm a long time Win 7 user. If Apple sort out their hardware line up I'll be heading for Mac land when 7 drops off support.