... but not for business. The mainstream free anti-virus solutions prohibit business use, unlike MSE.
I took out my 2005 Dell laptop to get it's last XP updates. I also got a notification telling me what I already knew about MS Security Essentials for XP; it can no longer be installed for XP, but would continue to be updated for awhile. Fine. What they didn't tell me was that it will constantly nag me, saying MSE is no longer supported, blah blah, and to "click here" for more info, telling me the same thing.
So I fixed it. I uninstalled MSE and went back to AVG.

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