Defender onboard vs Defender off net

swchuck

Honorable
Jan 30, 2013
13
0
10,510
My Defender will not work because of other virussoftware was on at one stage. Cannot get it all cleaned for Defender to work.
If I download a new Defender from nt will that work. How do I remove previous version.
or what is the best freeware that I should use for virus checking.