I had the same problem here (the 89% download one) as well multiple other
problems many users are having. I have made several posts to these
Defender
installation forums inclluding the fix that worked for me as follows
contained in my post to Steve Dodson from Microsoft:
Problem Solved. Here is what I had to do in addition to the steps Steve
Dodson and Sarah told me to do to uninstall then reinstall Defender:
1) Run CCleaner to clean the registry, etc and turn off active Trend Micro
virus scanning (I was doing this before but this step alone did not
provide
the fix).
2) Unintall my Yahoo browser and everything else related to yahoo. I got
this idea when I saw in another post that Yahoo can be a problem I
initially
did not think this fix would apply to me since I was signing onto Internet
Explorer with microsoft.com as my homepage when all the problems were
going
on.
I hope this might help you.
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